ARM: 9352/1: iwmmxt: Remove support for PJ4/PJ4B cores

PJ4 is a v7 core that incorporates a iWMMXt coprocessor. However, GCC
does not support this combination (its iWMMXt configuration always
implies v5te), and so there is no v6/v7 user space that actually makes
use of this, beyond generic support for things like setjmp() that
preserve/restore the iWMMXt register file using generic LDC/STC
instructions emitted in assembler. As [0] appears to imply, this logic
is triggered for the init process at boot, and so most user threads will
have a iWMMXt register context associated with it, even though it is
never used.

At this point, it is highly unlikely that such GCC support will ever
materialize (and Clang does not implement support for iWMMXt to begin
with).

This means that advertising iWMMXt support on these cores results in
context switch overhead without any associated benefit, and so it is
better to simply ignore the iWMMXt unit on these systems. So rip out the
support. Doing so also fixes the issue reported in [0] related to UNDEF
handling of co-processor #0/#1 instructions issued from user space
running in Thumb2 mode.

The PJ4 cores are used in four platforms: Armada 370/xp, Dove (Cubox,
d2plug), MMP2 (xo-1.75) and Berlin (Google TV). Out of these, only the
first is still widely used, but that one actually doesn't have iWMMXt
but instead has only VFPV3-D16, and so it is not impacted by this
change.

Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218427 [0]

Fixes: 8bcba70cb5c22 ("ARM: entry: Disregard Thumb undef exception ...")
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Reviewed-by: Jisheng Zhang <jszhang@kernel.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

Introduce cpu_dcache_is_aliasing() across all architectures

Introduce a generic way to query whether the data cache is virtually
aliased on all architectures. Its purpose is to ensure that subsystems
which are incompatible with virtually aliased data caches (e.g. FS_DAX)
can reliably query this.

For data cache aliasing, there are three scenarios dependending on the
architecture. Here is a breakdown based on my understanding:

A) The data cache is always aliasing:

* arc
* csky
* m68k (note: shared memory mappings are incoherent ? SHMLBA is missing there.)
* sh
* parisc

B) The data cache aliasing is statically known or depends on querying CPU
state at runtime:

* arm (cache_is_vivt() || cache_is_vipt_aliasing())
* mips (cpu_has_dc_aliases)
* nios2 (NIOS2_DCACHE_SIZE > PAGE_SIZE)
* sparc32 (vac_cache_size > PAGE_SIZE)
* sparc64 (L1DCACHE_SIZE > PAGE_SIZE)
* xtensa (DCACHE_WAY_SIZE > PAGE_SIZE)

C) The data cache is never aliasing:

* alpha
* arm64 (aarch64)
* hexagon
* loongarch (but with incoherent write buffers, which are disabled since
commit d23b7795 ("LoongArch: Change SHMLBA from SZ_64K to PAGE_SIZE"))
* microblaze
* openrisc
* powerpc
* riscv
* s390
* um
* x86

Require architectures in A) and B) to select ARCH_HAS_CPU_CACHE_ALIASING and
implement "cpu_dcache_is_aliasing()".

Architectures in C) don't select ARCH_HAS_CPU_CACHE_ALIASING, and thus
cpu_dcache_is_aliasing() simply evaluates to "false".

Note that this leaves "cpu_icache_is_aliasing()" to be implemented as future
work. This would be useful to gate features like XIP on architectures
which have aliasing CPU dcache-icache but not CPU dcache-dcache.

Use "cpu_dcache" and "cpu_cache" rather than just "dcache" and "cache"
to clarify that we really mean "CPU data cache" and "CPU cache" to
eliminate any possible confusion with VFS "dentry cache" and "page
cache".

Link: https://lore.kernel.org/lkml/20030910210416.GA24258@mail.jlokier.co.uk/
Link: https://lkml.kernel.org/r/20240215144633.96437-9-mathieu.desnoyers@efficios.com
Fixes: d92576f1167c ("dax: does not work correctly with virtual aliasing caches")
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Michael Sclafani <dm-devel@lists.linux.dev>
Cc: Mike Snitzer <snitzer@kernel.org>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

arch: define CONFIG_PAGE_SIZE_*KB on all architectures

Most architectures only support a single hardcoded page size. In order
to ensure that each one of these sets the corresponding Kconfig symbols,
change over the PAGE_SHIFT definition to the common one and allow
only the hardware page size to be selected.

Acked-by: Guo Ren <guoren@kernel.org>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Acked-by: Stafford Horne <shorne@gmail.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ubsan: Remove CONFIG_UBSAN_SANITIZE_ALL

For simplicity in splitting out UBSan options into separate rules,
remove CONFIG_UBSAN_SANITIZE_ALL, effectively defaulting to "y", which
is how it is generally used anyway. (There are no ":= y" cases beyond
where a specific file is enabled when a top-level ":= n" is in effect.)

Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Marco Elver <elver@google.com>
Cc: linux-doc@vger.kernel.org
Cc: linux-kbuild@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>

ARM: 9328/1: mm: try VMA lock-based page fault handling first

Attempt VMA lock-based page fault handling first, and fall back to the
existing mmap_lock-based handling if that fails, the ebizzy benchmark
shows 25% improvement on qemu with 2 cpus.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

ARM: mach-nspire: Rework support and directory structure

Having a platform need a mach-* directory should be seen as a negative,
it means the platform needs special non-standard handling. ARM64 support
does not allow mach-* directories at all. While we may not get to that
given all the non-standard architectures we support, we should still try
to get as close as we can and reduce the number of mach directories.

The mach-nspire/ directory and files, provides just one "feature":
having the kernel print the machine name if the DTB does not also contain
a "model" string (which they always do). To reduce the number of mach-*
directories let's do without that feature and remove this directory.

NOTE: The default l2c_aux_mask is now ~0 but these devices never have
this type of cache controller so this is safe.

Signed-off-by: Andrew Davis <afd@ti.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: mach-sunplus: Rework support and directory structure

Having a platform need a mach-* directory should be seen as a negative,
it means the platform needs special non-standard handling. ARM64 support
does not allow mach-* directories at all. While we may not get to that
given all the non-standard architectures we support, we should still try
to get as close as we can and reduce the number of mach directories.

The mach-sunplus/ directory and files, provides just one "feature":
having the kernel print the machine name if the DTB does not also contain
a "model" string (which they always do). To reduce the number of mach-*
directories let's do without that feature and remove this directory.

NOTE: The default l2c_aux_mask is now ~0 but these devices never have
this type of cache controller so this is safe.

Signed-off-by: Andrew Davis <afd@ti.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: mach-airoha: Rework support and directory structure

Having a platform need a mach-* directory should be seen as a negative,
it means the platform needs special non-standard handling. ARM64 support
does not allow mach-* directories at all. While we may not get to that
given all the non-standard architectures we support, we should still try
to get as close as we can and reduce the number of mach directories.

The mach-airoha/ directory, and files within, provide just one "feature":
having the kernel print the machine name if the DTB does not also contain
a "model" string (which they always do). To reduce the number of mach-*
directories let's do without that feature and remove this directory.

It also seems there was a copy/paste error and the "MEDIATEK_DT"
name was re-used in the DT_MACHINE_START macro. This may have caused
conflicts if this was built in a multi-arch configuration.

NOTE: The default l2c_aux_mask is now ~0 but these devices never have
this type of cache controller so this is safe.

Signed-off-by: Andrew Davis <afd@ti.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: mach-moxart: Move MOXA ART support into Kconfig.platforms

This removes the need for a dedicated Kconfig and empty mach directory.

Signed-off-by: Andrew Davis <afd@ti.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: mach-uniphier: Move Socionext UniPhier support into Kconfig.platforms

This removes the need for a dedicated Kconfig and empty mach directory.

Signed-off-by: Andrew Davis <afd@ti.com>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: mach-rda: Move RDA Micro support into Kconfig.platforms

This removes the need for a dedicated Kconfig and empty mach directory.

Signed-off-by: Andrew Davis <afd@ti.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: mach-asm9260: Move ASM9260 support into Kconfig.platforms

This removes the need for a dedicated Kconfig and mach directory.

Signed-off-by: Andrew Davis <afd@ti.com>
Reviewed-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: Kconfig: move platform selection into its own Kconfig file

Mostly just for better organization for now. This matches what is done on
some other platforms including ARM64. This also lets us start to reduce
the number of mach- directories that only exist to store the platform
selection.

Start with "Platform selection" and ARCH_VIRT.

Signed-off-by: Andrew Davis <afd@ti.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

mm, treewide: rename MAX_ORDER to MAX_PAGE_ORDER

commit 23baf831a32c ("mm, treewide: redefine MAX_ORDER sanely") has
changed the definition of MAX_ORDER to be inclusive. This has caused
issues with code that was not yet upstream and depended on the previous
definition.

To draw attention to the altered meaning of the define, rename MAX_ORDER
to MAX_PAGE_ORDER.

Link: https://lkml.kernel.org/r/20231228144704.14033-2-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

dma-direct: add a CONFIG_ARCH_HAS_DMA_ALLOC symbol

Instead of using arch_dma_alloc if none of the generic coherent
allocators are used, require the architectures to explicitly opt into
providing it. This will used to deal with the case of m68knommu and
coldfire where we can't do any coherent allocations whatsoever, and
also makes it clear that arch_dma_alloc is a last resort.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Greg Ungerer <gerg@linux-m68k.org>
Tested-by: Greg Ungerer <gerg@linux-m68k.org>

treewide: drop CONFIG_EMBEDDED

There is only one Kconfig user of CONFIG_EMBEDDED and it can be switched
to EXPERT or "if !ARCH_MULTIPLATFORM" (suggested by Arnd).

Link: https://lkml.kernel.org/r/20230816055010.31534-1-rdunlap@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com> [RISC-V]
Acked-by: Greg Ungerer <gerg@linux-m68k.org>
Acked-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> [powerpc]
Cc: Russell King <linux@armlinux.org.uk>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: Brian Cain <bcain@quicinc.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

arm/kexec: refactor for kernel/Kconfig.kexec

The kexec and crash kernel options are provided in the common
kernel/Kconfig.kexec. Utilize the common options and provide
the ARCH_SUPPORTS_ and ARCH_SELECTS_ entries to recreate the
equivalent set of KEXEC and CRASH options.

Link: https://lkml.kernel.org/r/20230712161545.87870-4-eric.devolder@oracle.com
Signed-off-by: Eric DeVolder <eric.devolder@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

arm/mm: Convert to using lock_mm_and_find_vma()

arm has an additional check for address < FIRST_USER_ADDRESS before
expanding the stack. Since FIRST_USER_ADDRESS is defined everywhere
(generally as 0), move that check to the generic expand_downwards().

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kbuild: Support flat DTBs install

In preparation to move Arm .dts files into sub-directories grouped
by vendor/family, the current flat tree of DTBs generated by
dtbs_install needs to be maintained. Moving the installed DTBs to
sub-directories would break various consumers using 'make dtbs_install'.

This is a NOP until sub-directories are introduced.

Signed-off-by: Rob Herring <robh@kernel.org>

ARM: cpu: Switch to arch_cpu_finalize_init()

check_bugs() is about to be phased out. Switch over to the new
arch_cpu_finalize_init() implementation.

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20230613224545.078124882@linutronix.de

arm: update in-source documentation references

The Arm documentation has moved to Documentation/arch/arm; update
references within arch/arm to match.

Cc: Russell King <linux@armlinux.org.uk>
Cc: Alim Akhtar <alim.akhtar@samsung.com>
Cc: Patrice Chotard <patrice.chotard@foss.st.com>
Cc: linux-doc@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-arch@vger.kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

ARM: smp: Switch to hotplug core state synchronization

Switch to the CPU hotplug core state tracking and synchronization
mechanim. No functional change intended.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Tested-by: Helge Deller <deller@gmx.de> # parisc
Tested-by: Guilherme G. Piccoli <gpiccoli@igalia.com> # Steam Deck
Link: https://lore.kernel.org/r/20230512205256.635326070@linutronix.de

arm: reword ARCH_FORCE_MAX_ORDER prompt and help text

Patch series "arch,mm: cleanup Kconfig entries for ARCH_FORCE_MAX_ORDER",
v3.

Several architectures have ARCH_FORCE_MAX_ORDER in their Kconfig and
they all have wrong and misleading prompt and help text for this option.

Besides, some define insane limits for possible values of
ARCH_FORCE_MAX_ORDER, some carefully define ranges only for a subset of
possible configurations, some make this option configurable by users for no
good reason.

This set updates the prompt and help text everywhere and does its best to
update actual definitions of ranges where applicable.

kbuild generated a bunch of false positives because it assigns -1 to
ARCH_FORCE_MAX_ORDER, hopefully this will be fixed soon.


This patch (of 14):

The prompt and help text of ARCH_FORCE_MAX_ORDER are not even close to
describe this configuration option.

Update both to actually describe what this option does.

Link: https://lkml.kernel.org/r/20230325060828.2662773-1-rppt@kernel.org
Link: https://lkml.kernel.org/r/20230324052233.2654090-1-rppt@kernel.org
Link: https://lkml.kernel.org/r/20230324052233.2654090-2-rppt@kernel.org
Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: David Miller <davem@davemloft.net>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Rich Felker <dalias@libc.org>
Cc: "Russell King (Oracle)" <linux@armlinux.org.uk>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm, treewide: redefine MAX_ORDER sanely

MAX_ORDER currently defined as number of orders page allocator supports:
user can ask buddy allocator for page order between 0 and MAX_ORDER-1.

This definition is counter-intuitive and lead to number of bugs all over
the kernel.

Change the definition of MAX_ORDER to be inclusive: the range of orders
user can ask from buddy allocator is 0..MAX_ORDER now.

[kirill@shutemov.name: fix min() warning]
Link: https://lkml.kernel.org/r/20230315153800.32wib3n5rickolvh@box
[akpm@linux-foundation.org: fix another min_t warning]
[kirill@shutemov.name: fixups per Zi Yan]
Link: https://lkml.kernel.org/r/20230316232144.b7ic4cif4kjiabws@box.shutemov.name
[akpm@linux-foundation.org: fix underlining in docs]
Link: https://lore.kernel.org/oe-kbuild-all/202303191025.VRCTk6mP-lkp@intel.com/
Link: https://lkml.kernel.org/r/20230315113133.11326-11-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Michael Ellerman <mpe@ellerman.id.au> [powerpc]
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Kconfig: introduce HAS_IOPORT option and select it as necessary

We introduce a new HAS_IOPORT Kconfig option to indicate support for I/O
Port access. In a future patch HAS_IOPORT=n will disable compilation of
the I/O accessor functions inb()/outb() and friends on architectures
which can not meaningfully support legacy I/O spaces such as s390.

The following architectures do not select HAS_IOPORT:

* ARC
* C-SKY
* Hexagon
* Nios II
* OpenRISC
* s390
* User-Mode Linux
* Xtensa

All other architectures select HAS_IOPORT at least conditionally.

The "depends on" relations on HAS_IOPORT in drivers as well as ifdefs
for HAS_IOPORT specific sections will be added in subsequent patches on
a per subsystem basis.

Co-developed-by: Arnd Bergmann <arnd@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@kernel.org>
Acked-by: Johannes Berg <johannes@sipsolutions.net> # for ARCH=um
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: oxnas: remove OXNAS support

Due to lack of maintainance and stall of development for a few years now,
and since no new features will ever be added upstream, remove support
for OX810 and OX820 ARM support.

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Daniel Golle <daniel@makrotopia.org>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Revert "ARM: mach-virt: Select PMUv3 driver by default"

This reverts commit 3b16f6268e660f15aed0bb97aefe87e893eb8882.

Selecting a Kconfig option that has its own set of dependencies tends to
end badly, and in this case 'randconfig' builds blew up on 32-bit ARM
where ARM_PMUV3 was being selecting with HW_PERF_EVENTS=n:

| drivers/perf/arm_pmuv3.c:68:5: error: use of undeclared identifier 'DTLB'
| [C(DTLB)][C(OP_READ)][C(RESULT_ACCESS)] = ARMV8_PMUV3_PERFCTR_L1D_TLB,
| ^
| fatal error: too many errors emitted, stopping now [-ferror-limit=]
| 20 errors generated.
|
| Kconfig warnings: (for reference only)
| WARNING: unmet direct dependencies detected for ARM_PMUV3
| Depends on [n]: PERF_EVENTS [=y] && HW_PERF_EVENTS [=n] && (ARM [=y] && CPU_V7 [=y] || ARM64)
| Selected by [y]:
| - ARCH_VIRT [=y] && ARCH_MULTI_V7 [=y] && PERF_EVENTS [=y]

As suggested by Marc, just drop the 'select' clause altogether by
reverting the patch which introduced it.

Link: https://lore.kernel.org/r/202303281539.zzI4vpw1-lkp@intel.com
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Suggested-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>

ARM: mach-virt: Select PMUv3 driver by default

Since 32bit guests are not unlikely to run on an ARMv8 host,
let's select the PMUv3 driver, which allows the PMU to be used
on such systems.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Zaid Al-Bassam <zalbassam@google.com>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20230317195027.3746949-9-zalbassam@google.com
Signed-off-by: Will Deacon <will@kernel.org>

gpiolib: remove empty asm/gpio.h files

The arm and sh versions of this file are identical to the generic
versions and can just be removed.

The drivers that actually use the sh3 specific version also include
cpu/gpio.h directly, with the exception of magicpanelr2, which is
easily fixed. This leaves coldfire as the only gpio driver
that needs something custom for gpiolib.

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com>

docs: move x86 documentation into Documentation/arch/

Move the x86 documentation under Documentation/arch/ as a way of cleaning
up the top-level directory and making the structure of our docs more
closely match the structure of the source directories it describes.

All in-kernel references to the old paths have been updated.

Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: linux-arch@vger.kernel.org
Cc: x86@kernel.org
Cc: Borislav Petkov <bp@alien8.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/lkml/20230315211523.108836-1-corbet@lwn.net/
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

ARM: remove CONFIG_UNUSED_BOARD_FILES

All unused board files are removed, so the Kconfig symbol is no
longer needed.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: 9289/1: Allow pre-ARMv5 builds with ld.lld 16.0.0 and newer

Commit 6a7ee50f8f56 ("ARM: disallow pre-ARMv5 builds with ld.lld")
prevented v4 or v4t kernels when ld.lld will link the kernel due to
inserting unsupported blx instructions.

ld.lld has been fixed in current main (16.0.0) to avoid inserting these
instructions by inserting position independent thunks instead. Allow
these configurations to be enabled when ld.lld 16.0.0 is used to link
the kernel.

Additionally, add a link to the upstream LLVM issue so that the reason
for this dependency is clearly documented.

Link: https://github.com/ClangBuiltLinux/linux/issues/964
Link: https://github.com/llvm/llvm-project/commit/6f9ff1beee9d12aca0c9caa9ae0051dc6d0a718c

Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

ARM: s3c: remove all s3c24xx support

The platform was deprecated in commit 6a5e69c7ddea ("ARM: s3c: mark
as deprecated and schedule removal") and can be removed. This includes
all files that are exclusively for s3c24xx and not shared with s3c64xx,
as well as the glue logic in Kconfig and the maintainer file entries.

Cc: Arnaud Patard <arnaud.patard@rtp-net.org>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Christer Weinigel <christer@weinigel.se>
Cc: Guillaume GOURAT <guillaume.gourat@nexvision.tv>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: Simtec Linux Team <linux@simtec.co.uk>
Cc: openmoko-kernel@lists.openmoko.org
Acked-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: sa1100: remove unused board files

The Cerf, H3100, Badge4, Hackkit, LART, NanoEngine, PLEB, Shannon and
Simpad machines were all marked as unused as there are no known users
left. Remove all of these, along with references to them in defconfig
files and drivers.

Four machines remain now: Assabet, Collie (Zaurus SL5500), iPAQ H3600
and Jornada 720, each of which had one person still using them, with
Collie also being supported in Qemu.

Cc: Peter Chubb <peter.chubb@unsw.edu.au>
Cc: Stefan Eletzhofer <stefan.eletzhofer@eletztrick.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Lee Jones <lee@kernel.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: 9281/1: improve Cortex A8/A9 errata help text

Document that !ARCH_MULTIPLATFORM is necessary because accessing
the the errata workaround registers may not work in non-secure
mode and mention that these erratas should be applied by the
bootloader instead.

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

ARM: iop32x: remove the platform

This was marked as unused in 5.19 and can now be removed

Cc: Lennert Buytenhek <kernel@wantstofly.org>
Cc: Martin Michlmayr <tbm@cyrius.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Wolfram Sang <wsa@kernel.org> # for I2C
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: cns3xxx: remove entire platform

cns3xxx was marked as unused a while ago, and gets removed
entirely now.

Acked-by: Krzysztof Hałasa <khalasa@piap.pl>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: remove CONFIG_UNUSED_BOARD_FILES

All unused board files are removed, so the Kconfig symbol is no
longer needed.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: disallow pre-ARMv5 builds with ld.lld

lld cannot build for ARMv4/v4T targets because it inserts 'blx' instructions
that are unsupported there:

ld.lld: warning: lld uses blx instruction, no object with architecture supporting feature detected

Add a Kconfig time dependency to prevent those targets from being
selected in randconfig builds.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Link: https://github.com/llvm/llvm-project/issues/50764
Link: https://github.com/ClangBuiltLinux/linux/issues/964
Link: https://lore.kernel.org/r/20221215162635.3750763-1-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

arm: Remove CONFIG_ARCH_NR_GPIO

CONFIG_ARCH_NR_GPIO is not used anymore, remove it.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

ARM: 9279/1: support function error injection

This enables HAVE_FUNCTION_ERROR_INJECTION by adding necessary
regs_set_return_value() and override_function_with_return().

Simply tested according to Documentation/fault-injection/fault-injection.rst.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

ARM: 9259/1: stacktrace: Convert stacktrace to generic ARCH_STACKWALK

Historically architectures have had duplicated code in their stack trace
implementations for filtering what gets traced. In order to avoid this
duplication some generic code has been provided using a new interface
arch_stack_walk(), enabled by selecting ARCH_STACKWALK in Kconfig, which
factors all this out into the generic stack trace code. Convert ARM to
use this common infrastructure.

When initializing the stack frame of the current task, arm64 uses
__builtin_frame_address(1) to initialize the frame pointer, skipping
arch_stack_walk(), see the commit c607ab4f916d ("arm64: stacktrace:
don't trace arch_stack_walk()"). Since __builtin_frame_address(1) does
not work on ARM, unwind_frame() is used to unwind the stack one layer
forward before calling walk_stackframe().

Signed-off-by: Li Huafei <lihuafei1@huawei.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

ARM: 9253/1: ubsan: select ARCH_HAS_UBSAN_SANITIZE_ALL

To enable UBSAN on ARM, this patch enables ARCH_HAS_UBSAN_SANITIZE_ALL
from arm confiuration. Basic kernel bootup test is passed on arm with
CONFIG_UBSAN_SANITIZE_ALL enabled.

[florian: rebased against v6.0-rc7]

Signed-off-by: Seung-Woo Kim <sw0312.kim@samsung.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

arch: mm: rename FORCE_MAX_ZONEORDER to ARCH_FORCE_MAX_ORDER

This Kconfig option is used by individual arch to set its desired
MAX_ORDER. Rename it to reflect its actual use.

Link: https://lkml.kernel.org/r/20220815143959.1511278-1-zi.yan@sent.com
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Zi Yan <ziy@nvidia.com>
Acked-by: Guo Ren <guoren@kernel.org> [csky]
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Catalin Marinas <catalin.marinas@arm.com> [arm64]
Acked-by: Huacai Chen <chenhuacai@kernel.org> [LoongArch]
Acked-by: Michael Ellerman <mpe@ellerman.id.au> [powerpc]
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Taichi Sugaya <sugaya.taichi@socionext.com>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: Qin Jian <qinjian@cqplus1.com>
Cc: Guo Ren <guoren@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Zankel <chris@zankel.net>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

crypto: Kconfig - submenus for arm and arm64

Move ARM- and ARM64-accelerated menus into a submenu under
the Crypto API menu (paralleling all the architectures).

Make each submenu always appear if the corresponding architecture
is supported. Get rid of the ARM_CRYPTO and ARM64_CRYPTO symbols.

The "ARM Accelerated" or "ARM64 Accelerated" entry disappears from:
General setup --->
Platform selection --->
Kernel Features --->
Boot options --->
Power management options --->
CPU Power Management --->
[*] ACPI (Advanced Configuration and Power Interface) Support --->
[*] Virtualization --->
[*] ARM Accelerated Cryptographic Algorithms --->
(or)
[*] ARM64 Accelerated Cryptographic Algorithms --->
...
-*- Cryptographic API --->
Library routines --->
Kernel hacking --->

and moves into the Cryptographic API menu, which now contains:
...
Accelerated Cryptographic Algorithms for CPU (arm) --->
(or)
Accelerated Cryptographic Algorithms for CPU (arm64) --->
[*] Hardware crypto devices --->
...

Suggested-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Robert Elliott <elliott@hpe.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

ARM: Drop CMDLINE_* dependency on ATAGS

On arm32, the configuration options to specify the kernel command line
type depend on ATAGS. However, the actual CMDLINE cofiguration option
does not depend on ATAGS, and the code that handles this is not specific
to ATAGS (see drivers/of/fdt.c:early_init_dt_scan_chosen()).

Hence users who desire to override the kernel command line on arm32 must
enable support for ATAGS, even on a pure-DT system. Other architectures
(arm64, loongarch, microblaze, nios2, powerpc, and riscv) do not impose
such a restriction.

Hence drop the dependency on ATAGS.

Fixes: bd51e2f595580fb6 ("ARM: 7506/1: allow for ATAGS to be configured out when DT support is selected")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: Drop CMDLINE_FORCE dependency on !ARCH_MULTIPLATFORM

On older platforms that boot an image with an appended DTB, or where
the boot loader has no support for updating chosen/bootargs, it is
common to rely on CMDLINE_FORCE.

While a fixed command line can make the kernel unbootable on other
platforms, it is not guaranteed to cause that. E.g. all Renesas boards
use the same chosen/bootargs in upstream DTS, which works fine if your
DHCP server hands out proper nfsroot parameters.

Fixes: 84fc863606239d8b ("ARM: make ARCH_MULTIPLATFORM user-visible")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: disallow PCI with MMU=n again

My cleanup patch allowed enabling PCI on MMU-less builds,
which breaks for at least one driver and is never required:

In file included from include/linux/irqchip/arm-gic-v3.h:604,
from drivers/pci/controller/pcie-iproc.c:17:
arch/arm/include/asm/arch_gicv3.h: In function 'write_ICC_EOIR1_EL1':
arch/arm/include/asm/arch_gicv3.h:44:9: error: implicit declaration of function 'write_sysreg' [-Werror=implicit-function-declaration]

Fixes: 6fd09c9afa49 ("ARM: Kconfig: clean up platform selection")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: footbridge: move isa-dma support into footbridge

The dma-isa.c was shared between footbridge and shark a long time ago,
but as shark was removed, it can be made footbridge specific again.

The fb_dma bits in turn are not used at all and can be removed.

All the ISA related files are now built into the platform regardless
of CONFIG_ISA, as they just refer to on-chip devices rather than actual
ISA cards.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: make ARCH_MULTIPLATFORM user-visible

Some options like CONFIG_DEBUG_UNCOMPRESS and CONFIG_CMDLINE_FORCE are
fundamentally incompatible with portable kernels but are currently allowed
in all configurations. Other options like XIP_KERNEL are essentially
useless after the completion of the multiplatform conversion.

Repurpose the existing CONFIG_ARCH_MULTIPLATFORM option to decide
whether the resulting kernel image is meant to be portable or not,
and using this to guard all of the known incompatible options.

This is similar to how the RISC-V kernel handles the CONFIG_NONPORTABLE
option (with the opposite polarity).

A few references to CONFIG_ARCH_MULTIPLATFORM were left behind by
earlier clanups and have to be removed now up.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: fix XIP_KERNEL dependencies

CONFIG_XIP_KERNEL does not work with any option that involves patching
the read-only kernel .text.

Since at least CONFIG_SMP_ON_UP is required in certain configurations,
flip the dependency to always allow the .text patching options but make
XIP_KERNEL have the dependency instead.

This is a prerequisite for allowing CONFIG_ARCH_MULTIPLATFORM to
be disabled.

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: Kconfig: clean up platform selection

The top-level platform selection is mostly meaningless these days after
almost everything is sorted below the CONFIG_ARCH_MULTIPLATFORM, with
the only exception being the 20+ year old StrongARM based machines.

Make this more consistent by removing the entire choice statement and
moving the StrongARM specific options into regular platform specific
Kconfig files.

The three platforms (footbridge, rpc and sa1100) are still mutually
exclusive and cannot coexist with other ARMv4/v5 machines, but since
there are only three of them and we will not add more, this can be
expressed using Kconfig 'depends on' statements.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: remove obsolete Makefile.boot infrastructure

There are a number of old Makefile.boot files that remain from the
multiplatform conversion, and three that are still in use.

These provide the "ZRELADDR", "PARAMS_PHYS" and "INITRD_PHYS" values
that are platform specific. It turns out that we can generally just
derive this from information that is available elsewhere:

- ZRELADDR is normally detected at runtime with the
CONFIG_AUTO_ZRELADDR flag, but also needed to be passed to
for 'make uImage'. In a multiplatform kernel, one always has
to pass this as the $(LOADADDR) variable, but in the StrongARM
kernels we can derive it from the sum of $(CONFIG_PHYS_OFFSET)
and $(TEXT_OFFSET) that are already known.

- PARAMS_PHYS and INITRD_PHYS are only used for bootpImage, which
in turn is only used for the pre-ATAGS 'param_struct' based boot
interface on StrongARM based machines with old boot loaders.
They can both be derived from CONFIG_PHYS_OFFSET and a machine
specific offset for the initrd, so all of the logic for these
can be part of arch/arm/boot/bootp/Makefile.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM/dma-mapping: use dma-direct unconditionally

Use dma-direct unconditionally on arm. It has already been used for
some time for LPAE and nommu configurations.

This mostly changes the streaming mapping implementation and the (simple)
coherent allocator for device that are DMA coherent. The existing
complex allocator for uncached mappings for non-coherent devices is still
used as is using the arch_dma_alloc/arch_dma_free hooks.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Andre Przywara <andre.przywara@arm.com> [highbank]
Tested-by: Marc Zyngier <maz@kernel.org>

ARM/dma-mapping: use the generic versions of dma_to_phys/phys_to_dma by default

Only the footbridge platforms provide their own DMA address translation
helpers, so switch to the generic version for all other platforms, and
consolidate the footbridge implementation to remove two levels of
indirection.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Marc Zyngier <maz@kernel.org>

mm/mmap: drop ARCH_HAS_VM_GET_PAGE_PROT

Now all the platforms enable ARCH_HAS_GET_PAGE_PROT. They define and
export own vm_get_page_prot() whether custom or standard
DECLARE_VM_GET_PAGE_PROT. Hence there is no need for default generic
fallback for vm_get_page_prot(). Just drop this fallback and also
ARCH_HAS_GET_PAGE_PROT mechanism.

Link: https://lkml.kernel.org/r/20220711070600.2378316-27-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

arm/mm: enable ARCH_HAS_VM_GET_PAGE_PROT

This enables ARCH_HAS_VM_GET_PAGE_PROT on the platform and exports
standard vm_get_page_prot() implementation via DECLARE_VM_GET_PAGE_PROT,
which looks up a private and static protection_map[] array. Subsequently
all __SXXX and __PXXX macros can be dropped which are no longer needed.

Link: https://lkml.kernel.org/r/20220711070600.2378316-24-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Brian Cain <bcain@quicinc.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Rich Felker <dalias@libc.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vineet Gupta <vgupta@kernel.org>
Cc: WANG Xuerui <kernel@xen0n.name>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

ARM: 9203/1: kconfig: fix MODULE_PLTS for KASAN with KASAN_VMALLOC

When we run out of module space address with ko insertion,
and with MODULE_PLTS, module would turn to try to find memory
from VMALLOC address space.

Unfortunately, with KASAN enabled, VMALLOC doesn't work without
KASAN_VMALLOC, thus select KASAN_VMALLOC by default.

8<--- cut here ---
Unable to handle kernel paging request at virtual address bd300860
[bd300860] *pgd=41cf1811, *pte=41cf26df, *ppte=41cf265f
Internal error: Oops: 80f [#1] PREEMPT SMP ARM
Modules linked in: hello(O+)
CPU: 0 PID: 89 Comm: insmod Tainted: G O 5.16.0-rc6+ #19
Hardware name: Generic DT based system
PC is at mmioset+0x30/0xa8
LR is at 0x0
pc : [<c077ed30>] lr : [<00000000>] psr: 20000013
sp : c451fc18 ip : bd300860 fp : c451fc2c
r10: f18042cc r9 : f18042d0 r8 : 00000000
r7 : 00000001 r6 : 00000003 r5 : 01312d00 r4 : f1804300
r3 : 00000000 r2 : 00262560 r1 : 00000000 r0 : bd300860
Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none
Control: 10c5387d Table: 43e9406a DAC: 00000051
Register r0 information: non-paged memory
Register r1 information: NULL pointer
Register r2 information: non-paged memory
Register r3 information: NULL pointer
Register r4 information: 4887-page vmalloc region starting at 0xf1802000 allocated at load_module+0x14f4/0x32a8
Register r5 information: non-paged memory
Register r6 information: non-paged memory
Register r7 information: non-paged memory
Register r8 information: NULL pointer
Register r9 information: 4887-page vmalloc region starting at 0xf1802000 allocated at load_module+0x14f4/0x32a8
Register r10 information: 4887-page vmalloc region starting at 0xf1802000 allocated at load_module+0x14f4/0x32a8
Register r11 information: non-slab/vmalloc memory
Register r12 information: non-paged memory
Process insmod (pid: 89, stack limit = 0xc451c000)
Stack: (0xc451fc18 to 0xc4520000)
fc00: f18041f0 c04803a4
fc20: c451fc44 c451fc30 c048053c c0480358 f1804030 01312cff c451fc64 c451fc48
fc40: c047f330 c0480500 f18040c0 c1b52ccc 00000001 c5be7700 c451fc74 c451fc68
fc60: f1802098 c047f300 c451fcb4 c451fc78 c026106c f180208c c4880004 00000000
fc80: c451fcb4 bf001000 c044ff48 c451fec0 f18040c0 00000000 c1b54cc4 00000000
fca0: c451fdf0 f1804268 c451fe64 c451fcb8 c0264e88 c0260d48 ffff8000 00007fff
fcc0: f18040c0 c025cd00 c451fd14 00000003 0157f008 f1804258 f180425c f1804174
fce0: f1804154 f180424c f18041f0 f180414c f1804178 f18041c0 bf0025d4 188a3fa8
fd00: 0000009e f1804170 f2b18000 c451ff10 c0d92e40 f180416c c451feec 00000001
fd20: 00000000 c451fec8 c451fe20 c451fed0 f18040cc 00000000 f17ea000 c451fdc0
fd40: 41b58ab3 c1387729 c0261c28 c047fb5c c451fe2c c451fd60 c0525308 c048033c
fd60: 188a3fb4 c3ccb090 c451fe00 c3ccb080 00000000 00000000 00016920 00000000
fd80: c02d0388 c047f55c c02d0388 00000000 c451fddc c451fda0 c02d0388 00000000
fda0: 41b58ab3 c13a72d0 c0524ff0 c1705f48 c451fdfc c451fdc0 c02d0388 c047f55c
fdc0: 00016920 00000000 00000003 c1bb2384 c451fdfc c3ccb080 c1bb2384 00000000
fde0: 00000000 00000000 00000000 00000000 c451fe1c c451fe00 c04e9d70 c1705f48
fe00: c1b54cc4 c1bbc71c c3ccb080 00000000 c3ccb080 00000000 00000003 c451fec0
fe20: c451fe64 c451fe30 c0525918 c0524ffc c451feb0 c1705f48 00000000 c1b54cc4
fe40: b78a3fd0 c451ff60 00000000 0157f008 00000003 c451fec0 c451ffa4 c451fe68
fe60: c0265480 c0261c34 c451feb0 7fffffff 00000000 00000002 00000000 c4880000
fe80: 41b58ab3 c138777b c02652cc c04803ec 000a0000 c451ff00 ffffff9c b6ac9f60
fea0: c451fed4 c1705f48 c04a4a90 b78a3fdc f17ea000 ffffff9c b6ac9f60 c0100244
fec0: f17ea21a f17ea300 f17ea000 00016920 f1800240 f18000ac f17fb7dc 01316000
fee0: 013161b0 00002590 01316250 00000000 00000000 00000000 00002580 00000029
ff00: 0000002a 00000013 00000000 0000000c 00000000 00000000 0157f004 c451ffb0
ff20: c1719be0 aed6f410 c451ff74 c451ff38 c0c4103c c0c407d0 c451ff84 c451ff48
ff40: 00000805 c02c8658 c1604230 c1719c30 00000805 0157f004 00000005 c451ffb0
ff60: c1719be0 aed6f410 c451ffac c451ff78 c0122130 c1705f48 c451ffac 0157f008
ff80: 00000006 0000005f 0000017b c0100244 c4880000 0000017b 00000000 c451ffa8
ffa0: c0100060 c02652d8 0157f008 00000006 00000003 0157f008 00000000 b6ac9f60
ffc0: 0157f008 00000006 0000005f 0000017b 00000000 00000000 aed85f74 00000000
ffe0: b6ac9cd8 b6ac9cc8 00030200 aecf2d60 a0000010 00000003 00000000 00000000
Backtrace:
[<c048034c>] (kasan_poison) from [<c048053c>] (kasan_unpoison+0x48/0x5c)
[<c04804f4>] (kasan_unpoison) from [<c047f330>] (__asan_register_globals+0x3c/0x64)
r5:01312cff r4:f1804030
[<c047f2f4>] (__asan_register_globals) from [<f1802098>] (_sub_I_65535_1+0x18/0xf80 [hello])
r7:c5be7700 r6:00000001 r5:c1b52ccc r4:f18040c0
[<f1802080>] (_sub_I_65535_1 [hello]) from [<c026106c>] (do_init_module+0x330/0x72c)
[<c0260d3c>] (do_init_module) from [<c0264e88>] (load_module+0x3260/0x32a8)
r10:f1804268 r9:c451fdf0 r8:00000000 r7:c1b54cc4 r6:00000000 r5:f18040c0
r4:c451fec0
[<c0261c28>] (load_module) from [<c0265480>] (sys_finit_module+0x1b4/0x1e8)
r10:c451fec0 r9:00000003 r8:0157f008 r7:00000000 r6:c451ff60 r5:b78a3fd0
r4:c1b54cc4
[<c02652cc>] (sys_finit_module) from [<c0100060>] (ret_fast_syscall+0x0/0x1c)
Exception stack(0xc451ffa8 to 0xc451fff0)
ffa0: 0157f008 00000006 00000003 0157f008 00000000 b6ac9f60
ffc0: 0157f008 00000006 0000005f 0000017b 00000000 00000000 aed85f74 00000000
ffe0: b6ac9cd8 b6ac9cc8 00030200 aecf2d60
r10:0000017b r9:c4880000 r8:c0100244 r7:0000017b r6:0000005f r5:00000006
r4:0157f008
Code: e92d4100 e1a08001 e1a0e003 e2522040 (a8ac410a)
---[ end trace df6e12843197b6f5 ]---

Signed-off-by: Lecopzer Chen <lecopzer.chen@mediatek.com>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

ARM: 9202/1: kasan: support CONFIG_KASAN_VMALLOC

Simply make shadow of vmalloc area mapped on demand.

Since the virtual address of vmalloc for Arm is also between
MODULE_VADDR and 0x100000000 (ZONE_HIGHMEM), which means the shadow
address has already included between KASAN_SHADOW_START and
KASAN_SHADOW_END.
Thus we need to change nothing for memory map of Arm.

This can fix ARM_MODULE_PLTS with KASan, support KASan for higmem
and support CONFIG_VMAP_STACK with KASan.

Signed-off-by: Lecopzer Chen <lecopzer.chen@mediatek.com>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

ARM: add CONFIG_UNUSED_BOARD_FILES

Based on the recent mailing list discussion, most board file support
has no remaining users and can be scheduled for removal early next
year.

If a board is still found to have users, it will remain for this round
but users are encouraged to migrate to devicetree based booting where
possible.

The timing is meant to ensure the next longterm supported kernel
still contains all the board files, giving another year of support
for potential users that did not speak up and would otherwise be
stuck on the v5.15.y longterm kernel from 2021.

Link: https://lore.kernel.org/all/CAK8P3a0Z9vGEQbVRBo84bSyPFM-LF+hs5w8ZA51g2Z+NsdtDQA@mail.gmail.com/
Link: https://docs.google.com/spreadsheets/d/1PL4dUUSieeXHzZhAn_Rnix32OTiCfN33sCQejpvI6ng/edit#gid=0
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: add ATAGS dependencies to non-DT platforms

There are a total of eight platforms that only suppor ATAGS based boot
with board files but no devicetree booting.

For dove, the DT support is part of the mvebu platform, which shares
driver but no code in arch/arm.

Most of these will never get converted to DT, and the majority of the
board files appear to be entirely unused already. There are still known
users on a few machines, and there may be interest in converting some
omap1, ep93xx or footbridge machines over in the future.

For the moment, just add a Kconfig dependency to hide these platforms
completely when CONFIG_ATAGS is disabled, and reorder the priority
of the options: Rather than offering to turn ATAGS off for platforms
that have DT support, make it a top-level setting that determines
which platforms are visible.

The s3c24xx platform supports one machine with DT support, but it
cannot be built without also including ATAGS support, and the
entire platform is scheduled for removal, so leaving the entire
platform behind a dependency seems good enough.

All defconfig files should keep working, as the option remains default
enabled.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: sunplus: Add initial support for Sunplus SP7021 SoC

This patch aims to add an initial support for Sunplus SP7021 SoC.

Signed-off-by: Qin Jian <qinjian@cqplus1.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

context_tracking: Split user tracking Kconfig

Context tracking is going to be used not only to track user transitions
but also idle/IRQs/NMIs. The user tracking part will then become a
separate feature. Prepare Kconfig for that.

[ frederic: Apply Max Filippov feedback. ]

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Neeraj Upadhyay <quic_neeraju@quicinc.com>
Cc: Uladzislau Rezki <uladzislau.rezki@sony.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Nicolas Saenz Julienne <nsaenz@kernel.org>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Cc: Yu Liao <liaoyu15@huawei.com>
Cc: Phil Auld <pauld@redhat.com>
Cc: Paul Gortmaker<paul.gortmaker@windriver.com>
Cc: Alex Belits <abelits@marvell.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>
Tested-by: Nicolas Saenz Julienne <nsaenzju@redhat.com>

ARM: omap1: enable multiplatform

With all the header files out of the way, and the clock driver
converted to the common framework, nothing stops us from building
OMAP together with the other platforms.

As usual, the decompressor support is a victim here, and is
only available when CONFIG_DEBUG_LL is configured for the
particular board.

Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: hpe: Introduce the HPE GXP architecture

The GXP is the HPE BMC SoC that is used in the majority
of current generation HPE servers. Traditionally the asic will
last multiple generations of server before being replaced.

Info about SoC:

HPE GXP is the name of the HPE Soc. This SoC is used to implement many BMC
features at HPE. It supports ARMv7 architecture based on the Cortex A9
core. It is capable of using an AXI bus to whicha memory controller is
attached. It has multiple SPI interfaces to connect boot flash and BIOS
flash. It uses a 10/100/1000 MAC for network connectivity. It has multiple
i2c engines to drive connectivity with a host infrastructure. There
currently are no public specifications but this process is being worked.

Previously there was a requirement to reset the EHCI controller for the
asic to boot. This functionality has been moved to the u-boot
bootloader.

Signed-off-by: Nick Hawkins <nick.hawkins@hpe.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: pxa: convert to multiplatform

PXA is now ready to be built into a single kernel with all the
other ARMv5 platforms, so change the Kconfig bit to finish it
off. The mach/uncompress.h support is the last bit that goes away,
getting replaced with the normal DEBUG_LL based approach.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: pxa: remove support for MTD_XIP

Using MTD-XIP does not work on multiplatform kernels because
it requires SoC specific register accesses to be done from
low-level flash handling functions in RAM while the rest of the
kernel sits in flash.

I found no evidence of anyone still actually using this feature,
so remove it from PXA to avoid spending a lot of time on
actually making it work.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: pxa: move plat-pxa to drivers/soc/

There are two drivers in arch/arm/plat-pxa: mfp and ssp. Both
of them should ideally not be needed at all, as there are
proper subsystems to replace them.

OTOH, they are self-contained and can simply be normal
SoC drivers, so move them over there to eliminate one more
of the plat-* directories.

Acked-by: Robert Jarzmik <robert.jarzmik@free.fr> (mach-pxa)
Acked-by: Lubomir Rintel <lkundrak@v3.sk> (mach-mmp)
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: omap1: fix build with no SoC selected

In a multiplatform randconfig kernel, one can have
CONFIG_ARCH_OMAP1 enabled, but none of the specific SoCs.
This leads to some build issues as the code is not
meant to deal with this configuration at the moment:

arch/arm/mach-omap1/io.c:86:20: error: unused function 'omap1_map_common_io' [-Werror,-Wunused-function]
arch/arm/mach-omap1/pm.h:113:2: error: "Power management for this processor not implemented yet" [-Werror,-W#warnings]

Use the same trick as on OMAP2 and guard the actual compilation
of platform code with another Makefile ifdef check based
on an option that depends on having at least one SoC enabled.

The io.c file still needs to get compiled to allow building
device drivers with a dependency on CONFIG_ARCH_OMAP1.

Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: omap1: move mach/*.h into mach directory

Most of the header files are no longer referenced from outside
arch/arm/mach-omap1, so move them all to that place directly
and change their users to use the new location.

The exceptions are:

- mach/compress.h is used by the core architecture code
- mach/serial.h is used by mach/compress.h

The mach/memory.h is empty and gets removed in the process,
avoiding the need for CONFIG_NEED_MACH_MEMORY_H.

Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: omap1: use pci_remap_iospace() for omap_cf

The ISA I/O space handling in omap_cf is incompatible with
PCI drivers in a multiplatform kernel, and requires a custom
mach/io.h.

Change the driver to use pci_remap_iospace() like PCI drivers do,
so the generic ioport access can work across platforms.

To actually use that code, we have to select CONFIG_PCI
here.

Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: omap: split up arch/arm/plat-omap/Kconfig

All the remaining features in here are either omap1
or omap2plus specific, so move them into the respective
Kconfig files.

Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: ixp4xx: enable multiplatform support

After all the work that Linus Walleij did on this platform, it can be
part of a generic kernel build as well.

Note that there are known bugs in little-endian mode on ixp4xx, and
no other ARMv5 platform at this point supports big-endian mode, or is
likely to in the future, so there is limited practical value in this,
but it helps with build testing and ixp4xx little-endian support may
get fixed in the future.

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: rework endianess selection

Choosing big-endian vs little-endian kernels in Kconfig has not worked
correctly since the introduction of CONFIG_ARCH_MULTIPLATFORM a long
time ago.

The problems is that CONFIG_BIG_ENDIAN depends on
ARCH_SUPPORTS_BIG_ENDIAN, which can set by any one platform
in the config, but would actually have to be supported by all
of them.

This was mostly ok for ARMv6/ARMv7 builds, since these are BE8 and
tend to just work aside from problems in nonportable device drivers.
For ARMv4/v5 machines, CONFIG_BIG_ENDIAN and CONFIG_ARCH_MULTIPLATFORM
were never set together, so this was disabled on all those machines
except for IXP4xx.

As IXP4xx can now become part of ARCH_MULTIPLATFORM, it seems better to
formalize this logic: all ARMv4/v5 platforms get an explicit dependency
on being either big-endian (ixp4xx) or little-endian (the rest). We may
want to fix ixp4xx in the future to support both, but it does not work
in LE mode at the moment.

For the ARMv6/v7 platforms, there are two ways this could be handled

a) allow both modes only for platforms selecting
'ARCH_SUPPORTS_BIG_ENDIAN' today, but only LE mode for the
others, given that these were added intentionally at some
point.

b) allow both modes everwhere, given that it was already possible
to build that way by e.g. selecting ARCH_VIRT, and that the
list is not an accurate reflection of which platforms may or
may not work.

Out of these, I picked b) because it seemed slighly more logical
to me.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: iop32x: enable multiplatform support

After iop32x was converted to the generic multi-irq entry
code, nothing really stops us from building it into a
generic kernel.

The two last headers can simply be removed, the mach/irqs.h
gets replaced with the sparse-irq intiialization from the
board specific .nr_irqs value, and the decompressor debug
output can use the debug_ll hack that all other platforms
use.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: s3c: enable s3c24xx multiplatform support

With the custom ISA I/O and the missing sparse-irq support
out of the way, s3c24xx can now be built into the same
kernel as all other ARM9 based platforms.

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: s3c24xx: convert to sparse-irq

As a final bit of preparation for converting to ARCH_MULTIPLATFORM,
change the interrupt handling for s3c24xx to use sparse IRQs.

Since the number of possible interrupts is already fixed and relatively
small per chip, just make it use all legacy interrupts preallocated
using the .nr_irqs field in the machine descriptor, rather than actually
allocating domains on the fly.

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: s3c24xx: remove support for ISA drivers on BAST PC/104

BAST is the one machine that theoretically supports unmodified ISA
drivers for hardware on its PC/104 connector, using a custom version of
the inb()/outb() and inw()/outw() macros.

This is incompatible with the generic version used in asm/io.h, and
can't easily be used in a multiplatform kernel.

Removing the special case for 16-bit I/O port access on BAST gets us
closer to multiplatform, at the expense of any PC/104 users with 16-bit
cards having to either use an older kernel or modify their ISA drivers
to manually ioremap() the area and use readw()/write() in place of
inw()/outw(). Either way is probably ok, given that there is a
recurring discussion about dropping s3c24xx altogether, and many
traditional ISA drivers are already gone.

Machines other than BAST already have no support for ISA drivers, though a
couple of them do map one of the external chip-selects into the ISA port
range, using the same address for 8-bit and 16-bit I/O. It is unlikely
that anything actually uses this mapping, but it's also easy to keep
this working by mapping it to the normal platform-independent PCI I/O
base that is otherwise unused on s3c24xx.

The mach/map-base.h file is no longer referenced in global headers and
can be moved into the platform directory.

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: dove: multiplatform support

The dove platform is now ready to be enabled for multiplatform
support, this patch does the switch over by modifying the Kconfig file,
the defconfig and removing the last mach/*.h header that becomes obsolete
with this.

This work was originally done in 2015 as all the ARMv7 machiens
gove moved over to multiplatform builds, but at the time it conflicted
with some patches that Russell was trying to upstream, so we
left it at that.

I hope that there is no longer a need to keep dove separate from the
rest, so we can either add it to the other ARMv7 platforms, or just
replace it with the DT based platform code for the same hardware
in mach-mvebu and remove mach-dove entirely.

Acked-by: Andrew Lunn <andrew@lunn.ch>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Cc: Gregory Clement <gregory.clement@bootlin.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: ep93xx: multiplatform support

With the clock support and the interrupts out of the way, ep93xx can be
compiled into the same kernel image as the other ARMv4/v5 platforms. The
last obstacle are the two workarounds for broken boot loaders that
require us to re-initialize the ethernet controller and/or the watchdog
on certain machines.

Move this code into the decompressor sources directly, checking for
each possibly affected machine individually.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: ep93xx: enable SPARSE_IRQ

Without CONFIG_SPARSE_IRQ, we rely on mach/irqs.h to define NR_IRQS
globally. Do the minimal conversion by setting .nr_irqs in each
machine descriptor.

Only the vision_ep9307 machine has extra IRQs for GPIOs, so make
.nr_irqs the original value there, while using the plain NR_EP93XX_IRQS
everywhere else.

Cc: Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Hubert Feurstein <hubert.feurstein@contec.at>
Cc: Lukasz Majewski <lukma@denx.de>
Tested-by: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: versatile: move integrator/realview/vexpress to versatile

These are all fairly small platforms by now, and they are
closely related. Just move them all into a single directory.

Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Liviu Dudau <liviu.dudau@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Tested-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: 9206/1: A9: Add ARM ERRATA 764319 workaround (Updated)

Enable the workaround for the 764319 Cortex A-9 erratum.
CP14 read accesses to the DBGPRSR and DBGOSLSR registers generate an
unexpected Undefined Instruction exception when the DBGSWENABLE external
pin is set to 0, even when the CP14 accesses are performed from a
privileged mode. The work around catches the exception in a way
the kernel does not stop execution with the use of undef_hook. This
has been found to effect the HPE GXP SoC.

Signed-off-by: Nick Hawkins <nick.hawkins@hpe.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

dma-mapping: remove CONFIG_DMA_REMAP

CONFIG_DMA_REMAP is used to build a few helpers around the core
vmalloc code, and to use them in case there is a highmem page in
dma-direct, and to make dma coherent allocations be able to use
non-contiguous pages allocations for DMA allocations in the dma-iommu
layer.

Right now it needs to be explicitly selected by architectures, and
is only done so by architectures that require remapping to deal
with devices that are not DMA coherent. Make it unconditional for
builds with CONFIG_MMU as it is very little extra code, but makes
it much more likely that large DMA allocations succeed on x86.

This fixes hot plugging a NVMe thunderbolt SSD for me, which tries
to allocate a 1MB buffer that is otherwise hard to obtain due to
memory fragmentation on a heavily used laptop.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>

Revert "ARM: rethook: Add rethook arm implementation"

This reverts commit 515a49173b80a4aabcbad9a4fa2a247042378ea1.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>

ARM: rethook: Add rethook arm implementation

Add rethook arm implementation. Most of the code has been copied from
kretprobes on arm.
Since the arm's ftrace implementation is a bit special, this needs a
special care using from fprobe.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Tested-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/164735289643.1084943.15184590256680485720.stgit@devnote2

ARM: remove support for NOMMU ARMv4/v5

It is possible to build MMU-less kernels for Cortex-M base
microcrontrollers as well as a couple of older platforms that
have not been converted to CONFIG_ARCH_MULTIPLATFORM,
specifically ep93xx, footbridge, dove, sa1100 and s3c24xx.

It seems unlikely that anybody has tested those configurations
in recent years, as even building them is frequently broken.
A patch I submitted caused another build time regression
in this configuration. I sent a patch for that, but it seems
better to also remove the option entirely, leaving ARMv7-M
as the only supported Arm NOMMU target for simplicity.

A couple of platforms have dependencies on CONFIG_MMU, those
can all be removed now. Notably, mach-integrator tries to
support MMU-less CPU cores, but those have not actually been
selectable for a long time.

This addresses several build failures in randconfig builds that
have accumulated over the years.

Cc: Vladimir Murzin <vladimir.murzin@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: fix building NOMMU ARMv4/v5 kernels

The removal of the old-style irq entry broke obscure NOMMU
configurations on machines that have an MMU:

ld.lld: error: undefined symbol: generic_handle_arch_irq
referenced by kernel/entry-armv.o:(__irq_svc) in archive arch/arm/built-in.a

A follow-up patch to convert nvic to the generic_handle_arch_irq()
could have fixed this by removing the Kconfig conditional, but did
it differently.

Change the Kconfig logic so ARM machines now unconditionally
enable the feature.

I have also submitted a patch to remove support for the configurations
that broke, but fixing the regression first is a trivial and correct
change.

Reported-by: kernel test robot <lkp@intel.com>
Fixes: 54f481a2308e ("ARM: remove old-style irq entry")
Fixes: 52d240871760 ("irqchip: nvic: Use GENERIC_IRQ_MULTI_HANDLER")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

ARM: Add basic support for Airoha EN7523 SoC

EN7523 is an armv8 based silicon used inside broadband access type devices
such as xPON and xDSL. It shares various silicon blocks with MediaTek
silicon such as the MT7622.

Add basic support for Airoha EN7523, enough for booting to console.

The UART is basically 8250-compatible, except for the clock selection.
A clock-frequency value is synthesized to get this to run at 115200 bps.

Signed-off-by: John Crispin <john@phrozen.org>
Signed-off-by: Bert Vermeulen <bert@biot.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20220130145116.88406-4-nbd@nbd.name
Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>

ARM: ixp4xx: Convert to SPARSE_IRQ and P2V

Turn on sparse IRQs and patch-physical-to-virtual for IXP4xx
as this is required for multiplatform. Drop the PHYS_OFFSET as
we are now using P2V.

Tested and works like a charm on my systems.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20220211223238.648934-14-linus.walleij@linaro.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

ARM: ixp4xx: Drop custom DMA coherency and bouncing

The new PCI driver does not need any of this stuff, so just
drop it.

Cc: iommu@lists.linux-foundation.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20220211223238.648934-12-linus.walleij@linaro.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

ARM: ixp4xx: Delete old PCI driver

We are just using the new PCI driver in the proper PCI host
drivers folder: drivers/pci/controller/pci-ixp4xx.c.

The new driver does not support indirect PCI but it has
turned out noone is using this. If the feature is desired
we have ways to implement it, suggested by John Linville.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20220211223238.648934-4-linus.walleij@linaro.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Revert "ARM: 9144/1: forbid ftrace with clang and thumb2_kernel"

This reverts commit ecb108e3e3f7c692082b7c6fce41779c3835854a.

Clang + Thumb2 with ftrace is now supported.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>

ARM: ftrace: enable the graph tracer with the EABI unwinder

Enable the function graph tracer in combination with the EABI unwinder,
so that Thumb2 builds or Clang ARM builds can make use of it.

This involves using the unwinder to locate the return address of an
instrumented function on the stack, so that it can be overridden and
made to refer to the ftrace handling routines that need to be called at
function return.

Given that for these builds, it is not guaranteed that the value of the
link register is stored on the stack, fall back to the stack slot that
will be used by the ftrace exit code to restore LR in the instrumented
function's execution context.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>

ARM: assembler: define a Kconfig symbol for group relocation support

Nathan reports the group relocations go out of range in pathological
cases such as allyesconfig kernels, which have little chance of actually
booting but are still used in validation.

So add a Kconfig symbol for this feature, and make it depend on
!COMPILE_TEST.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

ARM: mm: switch to swapper_pg_dir early for vmap'ed stack

When onlining a CPU, switch to swapper_pg_dir as soon as possible so
that it is guaranteed that the vmap'ed stack is mapped before it is
used.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

ARM: 9177/1: disable vmap'ed stacks on suspend-capable SMP configs

There are several reports about the new vmap'ed stacks code breaking
suspend/resume on Exynos, Renesas and Tegra SMP platforms. While this is
under investigation, let's disable the vmap'ed stacks feature for the
time being for SMP configurations that have suspend/resume enabled.

[0] https://lore.kernel.org/linux-arm-kernel/20211122092816.2865873-8-ardb@kernel.org/

Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

ARM: v7m: enable support for IRQ stacks

Enable support for IRQ stacks on !MMU, and add the code to the IRQ entry
path to switch to the IRQ stack if not running from it already.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M

ARM: implement THREAD_INFO_IN_TASK for uniprocessor systems

On UP systems, only a single task can be 'current' at the same time,
which means we can use a global variable to track it. This means we can
also enable THREAD_INFO_IN_TASK for those systems, as in that case,
thread_info is accessed via current rather than the other way around,
removing the need to store thread_info at the base of the task stack.
This, in turn, permits us to enable IRQ stacks and vmap'ed stacks on UP
systems as well.

To partially mitigate the performance overhead of this arrangement, use
a ADD/ADD/LDR sequence with the appropriate PC-relative group
relocations to load the value of current when needed. This means that
accessing current will still only require a single load as before,
avoiding the need for a literal to carry the address of the global
variable in each function. However, accessing thread_info will now
require this load as well.

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M

ARM: use TLS register for 'current' on !SMP as well

Enable the use of the TLS register to hold the 'current' pointer also on
non-SMP configurations that target v6k or later CPUs. This will permit
the use of THREAD_INFO_IN_TASK as well as IRQ stacks and vmap'ed stacks
for such configurations.

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M

ARM: remove old-style irq entry

The last user of arch_irq_handler_default is gone now, so the
entry-macro-multi.S file and all references to mach/entry-macro.S can
be removed, as well as the asm_do_IRQ() entrypoint into the interrupt
handling routines implemented in C.

Note: The ARMv7-M entry still uses its own top-level IRQ entry, calling
nvic_handle_irq() from assembly. This could be changed to go through
generic_handle_arch_irq() as well, but it's unclear to me if there are
any benefits.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
[ardb: keep irq_handler macro as it carries all the IRQ stack handling]
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

ARM: iop32x: use GENERIC_IRQ_MULTI_HANDLER

iop32x uses the entry-macro.S file for both the IRQ entry and for
hooking into the arch_ret_to_user code path. This is done because the
cp6 registers have to be enabled before accessing any of the interrupt
controller registers but have to be disabled when running in user space.

There is also a lazy-enable logic in cp6.c, but during a hardirq, we
know it has to be enabled.

Both the cp6-enable code and the code to read the IRQ status can be
lifted into the normal generic_handle_arch_irq() path, but the
cp6-disable code has to remain in the user return code. As nothing
other than iop32x uses this hook, just open-code it there with an
ifdef for the platform that can eventually be removed when iop32x
has reached the end of its life.

The cp6-enable path in the IRQ entry has an extra cp_wait barrier that
the trap version does not have, but it is harmless to do it in both
cases to simplify the logic here at the cost of a few extra cycles
for the trap.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M

ARM: footbridge: use GENERIC_IRQ_MULTI_HANDLER

Footbridge still uses the classic IRQ entry path in assembler,
but this is easily converted into an equivalent C version.

In this case, the correlation between IRQ numbers and bits in
the status register is non-obvious, and the priorities are
handled by manually checking each bit in a static order,
re-reading the status register after each handled event.

I moved the code into the new file and edited the syntax without
changing this sequence to keep the behavior as close as possible
to what it traditionally did.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

ARM: riscpc: use GENERIC_IRQ_MULTI_HANDLER

This is one of the last platforms using the old entry path.
While this code path is spread over a few files, it is fairly
straightforward to convert it into an equivalent C version,
leaving the existing algorithm and all the priority handling
the same.

Unlike most irqchip drivers, this means reading the status
register(s) in a loop and always handling the highest-priority
irq first.

The IOMD_IRQREQC and IOMD_IRQREQD registers are not actaully
used here, but I left the code in place for the time being,
to keep the conversion as direct as possible. It could be
removed in a cleanup on top.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
[ardb: drop obsolete IOMD_IRQREQC/IOMD_IRQREQD handling]
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M

ARM: implement support for vmap'ed stacks

Wire up the generic support for managing task stack allocations via vmalloc,
and implement the entry code that detects whether we faulted because of a
stack overrun (or future stack overrun caused by pushing the pt_regs array)

While this adds a fair amount of tricky entry asm code, it should be
noted that it only adds a TST + branch to the svc_entry path. The code
implementing the non-trivial handling of the overflow stack is emitted
out-of-line into the .text section.

Since on ARM, we rely on do_translation_fault() to keep PMD level page
table entries that cover the vmalloc region up to date, we need to
ensure that we don't hit such a stale PMD entry when accessing the
stack. So we do a dummy read from the new stack while still running from
the old one on the context switch path, and bump the vmalloc_seq counter
when PMD level entries in the vmalloc range are modified, so that the MM
switch fetches the latest version of the entries.

Note that we need to increase the per-mode stack by 1 word, to gain some
space to stash a GPR until we know it is safe to touch the stack.
However, due to the cacheline alignment of the struct, this does not
actually increase the memory footprint of the struct stack array at all.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Keith Packard <keithpac@amazon.com>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M

ARM: run softirqs on the per-CPU IRQ stack

Now that we have enabled IRQ stacks, any softIRQs that are handled over
the back of a hard IRQ will run from the IRQ stack as well. However, any
synchronous softirq processing that happens when re-enabling softIRQs
from task context will still execute on that task's stack.

Since any call to local_bh_enable() at any level in the task's call
stack may trigger a softIRQ processing run, which could potentially
cause a task stack overflow if the combined stack footprints exceed the
stack's size, let's run these synchronous invocations of do_softirq() on
the IRQ stack as well.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Keith Packard <keithpac@amazon.com>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M

ARM: implement IRQ stacks

Now that we no longer rely on the stack pointer to access the current
task struct or thread info, we can implement support for IRQ stacks
cleanly as well.

Define a per-CPU IRQ stack and switch to this stack when taking an IRQ,
provided that we were not already using that stack in the interrupted
context. This is never the case for IRQs taken from user space, but ones
taken while running in the kernel could fire while one taken from user
space has not completed yet.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Keith Packard <keithpac@amazon.com>
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M

ARM: stackprotector: prefer compiler for TLS based per-task protector

Currently, we implement the per-task stack protector for ARM using a GCC
plugin, due to lack of native compiler support. However, work is
underway to get this implemented in the compiler, which means we will be
able to deprecate the GCC plugin at some point.

In the meantime, we will need to support both, where the native compiler
implementation is obviously preferred. So let's wire this up in Kconfig
and the Makefile.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M

mm/hugetlb: generalize ARCH_WANT_GENERAL_HUGETLB

ARCH_WANT_GENERAL_HUGETLB config has duplicate definitions on platforms
that subscribe it. Instead make it a generic config option which can be
selected on applicable platforms when required.

Link: https://lkml.kernel.org/r/1643718465-4324-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

usercopy: Check valid lifetime via stack depth

One of the things that CONFIG_HARDENED_USERCOPY sanity-checks is whether
an object that is about to be copied to/from userspace is overlapping
the stack at all. If it is, it performs a number of inexpensive
bounds checks. One of the finer-grained checks is whether an object
crosses stack frames within the stack region. Doing this on x86 with
CONFIG_FRAME_POINTER was cheap/easy. Doing it with ORC was deemed too
heavy, and was left out (a while ago), leaving the courser whole-stack
check.

The LKDTM tests USERCOPY_STACK_FRAME_TO and USERCOPY_STACK_FRAME_FROM
try to exercise these cross-frame cases to validate the defense is
working. They have been failing ever since ORC was added (which was
expected). While Muhammad was investigating various LKDTM failures[1],
he asked me for additional details on them, and I realized that when
exact stack frame boundary checking is not available (i.e. everything
except x86 with FRAME_POINTER), it could check if a stack object is at
least "current depth valid", in the sense that any object within the
stack region but not between start-of-stack and current_stack_pointer
should be considered unavailable (i.e. its lifetime is from a call no
longer present on the stack).

Introduce ARCH_HAS_CURRENT_STACK_POINTER to track which architectures
have actually implemented the common global register alias.

Additionally report usercopy bounds checking failures with an offset
from current_stack_pointer, which may assist with diagnosing failures.

The LKDTM USERCOPY_STACK_FRAME_TO and USERCOPY_STACK_FRAME_FROM tests
(once slightly adjusted in a separate patch) pass again with this fixed.

[1] https://github.com/kernelci/kernelci-project/issues/84

Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mm@kvack.org
Reported-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
---
v1: https://lore.kernel.org/lkml/20220216201449.2087956-1-keescook@chromium.org
v2: https://lore.kernel.org/lkml/20220224060342.1855457-1-keescook@chromium.org
v3: https://lore.kernel.org/lkml/20220225173345.3358109-1-keescook@chromium.org
v4: - improve commit log (akpm)

ftrace: Have architectures opt-in for mcount build time sorting

First S390 complained that the sorting of the mcount sections at build
time caused the kernel to crash on their architecture. Now PowerPC is
complaining about it too. And also ARM64 appears to be having issues.

It may be necessary to also update the relocation table for the values
in the mcount table. Not only do we have to sort the table, but also
update the relocations that may be applied to the items in the table.

If the system is not relocatable, then it is fine to sort, but if it is,
some architectures may have issues (although x86 does not as it shifts all
addresses the same).

Add a HAVE_BUILDTIME_MCOUNT_SORT that an architecture can set to say it is
safe to do the sorting at build time.

Also update the config to compile in build time sorting in the sorttable
code in scripts/ to depend on CONFIG_BUILDTIME_MCOUNT_SORT.

Link: https://lore.kernel.org/all/944D10DA-8200-4BA9-8D0A-3BED9AA99F82@linux.ibm.com/
Link: https://lkml.kernel.org/r/20220127153821.3bc1ac6e@gandalf.local.home

Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Yinan Liu <yinan@linux.alibaba.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Reported-by: Sachin Sant <sachinp@linux.ibm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com> [arm64]
Tested-by: Sachin Sant <sachinp@linux.ibm.com>
Fixes: 72b3942a173c ("scripts: ftrace - move the sort-processing in ftrace_init")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

ARM: 9166/1: Support KFENCE for ARM

Add architecture specific implementation details for KFENCE and enable
KFENCE on ARM. In particular, this implements the required interface in
<asm/kfence.h>.

KFENCE requires that attributes for pages from its memory pool can
individually be set. Therefore, force the kfence pool to be mapped
at page granularity.

Testing this patch using the testcases in kfence_test.c and all passed
with or without ARM_LPAE.

Acked-by: Marco Elver <elver@google.com>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

futex: Remove futex_cmpxchg detection

Now that all architectures have a working futex implementation in any
configuration, remove the runtime detection code.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Acked-by: Vineet Gupta <vgupta@kernel.org>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Link: https://lore.kernel.org/r/20211026100432.1730393-2-arnd@kernel.org

ARM: samsung: Remove HAVE_S3C2410_I2C and use direct dependencies

A separate Kconfig option HAVE_S3C2410_I2C for Samsung SoCs is not
really needed and the i2c-s3c24xx driver can depend on Samsung ARM
architectures instead. This also enables i2c-s3c2410 for arm64 Exynos
SoCs, which is required for example by Exynos850.

This is basically continuation of work made in following commits:
- commit d96890fca9fd ("rtc: s3c: remove HAVE_S3C_RTC in favor of
direct dependencies")
- commit 7dd3cae90d85 ("ARM: samsung: remove HAVE_S3C2410_WATCHDOG and
use direct dependencies")

Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
Link: https://lore.kernel.org/r/20211121150558.21801-2-semen.protsenko@linaro.org
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>

kmap_local: don't assume kmap PTEs are linear arrays in memory

The kmap_local conversion broke the ARM architecture, because the new
code assumes that all PTEs used for creating kmaps form a linear array
in memory, and uses array indexing to look up the kmap PTE belonging to
a certain kmap index.

On ARM, this cannot work, not only because the PTE pages may be
non-adjacent in memory, but also because ARM/!LPAE interleaves hardware
entries and extended entries (carrying software-only bits) in a way that
is not compatible with array indexing.

Fortunately, this only seems to affect configurations with more than 8
CPUs, due to the way the per-CPU kmap slots are organized in memory.

Work around this by permitting an architecture to set a Kconfig symbol
that signifies that the kmap PTEs do not form a lineary array in memory,
and so the only way to locate the appropriate one is to walk the page
tables.

Link: https://lore.kernel.org/linux-arm-kernel/20211026131249.3731275-1-ardb@kernel.org/
Link: https://lkml.kernel.org/r/20211116094737.7391-1-ardb@kernel.org
Fixes: 2a15ba82fa6c ("ARM: highmem: Switch to generic kmap atomic")
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reported-by: Quanyang Wang <quanyang.wang@windriver.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ep93xx: clock: convert in-place to COMMON_CLK

Converted in-place without moving file to drivers/clk.

tested on ts7250 (EP9302).

Only setting rate and change parent tested for, as they
are missing on ts7250:
- video
- I2S
- ADC/KEYPAD
- PWM

Only video and I2S clock are interesting, as they are
GATE + double DIV + MUX, all other are pretty much
common but require ep93xx_syscon_swlocked_write to set
registers.

Signed-off-by: Nikita Shubin <nikita.shubin@maquefel.me>
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Tested-by: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Acked-by: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Link: https://lore.kernel.org/r/20211018103105.146380-3-alexander.sverdlin@gmail.com'
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

rtc: s3c: remove HAVE_S3C_RTC in favor of direct dependencies

The config HAVE_S3C_RTC is not really needed since we can simply just
add the dependencies directly to RTC_DRV_S3C. Also, one less config to
keep track of!

Signed-off-by: Will McVicker <willmcvicker@google.com>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20211013212256.3425889-1-willmcvicker@google.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>

ARM: 9146/1: RiscPC needs older gcc version

Attempting to build mach-rpc with gcc-9 or higher, or with any version
of clang results in a build failure, like:

arm-linux-gnueabi-gcc-11.1.0: error: unrecognized -march target: armv3m
arm-linux-gnueabi-gcc-11.1.0: note: valid arguments are: armv4 armv4t armv5t armv5te armv5tej armv6 armv6j armv6k armv6z armv6kz armv6zk armv6t2 armv6-m armv6s-m armv7 armv7-a armv7ve armv7-r armv7-m armv7e-m armv8-a armv8.1-a armv8.2-a armv8.3-a armv8.4-a armv8.5-a armv8.6-a armv8-m.base armv8-m.main armv8-r armv8.1-m.main iwmmxt iwmmxt2; did you mean 'armv4'?

Building with gcc-5 also fails in at least one of these ways:

/tmp/cczZoCcv.s:68: Error: selected processor does not support `bx lr' in ARM mode
drivers/tty/vt/vt_ioctl.c:958:1: internal compiler error: Segmentation fault

Handle this in Kconfig so we don't run into this with randconfig
builds, allowing only gcc-6 through gcc-8.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

ARM: 9144/1: forbid ftrace with clang and thumb2_kernel

clang fails to build kernels with THUMB2 and FUNCTION_TRACER
enabled when there is any inline asm statement containing
the frame pointer register r7:

arch/arm/mach-exynos/mcpm-exynos.c:154:2: error: inline asm clobber list contains reserved registers: R7 [-Werror,-Winline-asm]
arch/arm/probes/kprobes/actions-thumb.c:449:3: error: inline asm clobber list contains reserved registers: R7 [-Werror,-Winline-asm]

Apparently gcc should also have warned about this, and the
configuration is actually invalid, though there is some
disagreement on the bug trackers about this.

Link: https://bugs.llvm.org/show_bug.cgi?id=45826
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94986

Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

ARM: 9143/1: add CONFIG_PHYS_OFFSET default values

For platforms that are not yet converted to ARCH_MULTIPLATFORM,
we can disable CONFIG_ARM_PATCH_PHYS_VIRT, which in turn requires
setting a correct address here.

As we actualy know what all the values are supposed to be based
on the old mach/memory.h header file contents (from git history),
we can just add them here.

This also solves a problem in Kconfig where 'make randconfig'
fails to continue if no number is selected for a 'hex' option.
Users can still override the number at configuration time, e.g.
when the memory visible to the kernel starts at a nonstandard
address on some machine, but it should no longer be required
now.

I originally posted this back in 2016, but the problem still
persists. The patch has gotten much simpler though, as almost
all platforms rely on ARM_PATCH_PHYS_VIRT now.

Link: https://lore.kernel.org/linux-arm-kernel/1455804123-2526139-5-git-send-email-arnd@arndb.de/

Acked-by: Nicolas Pitre <nico@fluxnic.net>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

ARM: smp: Enable THREAD_INFO_IN_TASK

Now that we no longer rely on thread_info living at the base of the task
stack to be able to access the 'current' pointer, we can wire up the
generic support for moving thread_info into the task struct itself.

Note that this requires us to update the cpu field in thread_info
explicitly, now that the core code no longer does so. Ideally, we would
switch the percpu code to access the cpu field in task_struct instead,
but this unleashes #include circular dependency hell.

Co-developed-by: Keith Packard <keithpac@amazon.com>
Signed-off-by: Keith Packard <keithpac@amazon.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Amit Daniel Kachhap <amit.kachhap@arm.com>

ARM: smp: Store current pointer in TPIDRURO register if available

Now that the user space TLS register is assigned on every return to user
space, we can use it to keep the 'current' pointer while running in the
kernel. This removes the need to access it via thread_info, which is
located at the base of the stack, but will be moved out of there in a
subsequent patch.

Use the __builtin_thread_pointer() helper when available - this will
help GCC understand that reloading the value within the same function is
not necessary, even when using the per-task stack protector (which also
generates accesses via the TLS register). For example, the generated
code below loads TPIDRURO only once, and uses it to access both the
stack canary and the preempt_count fields.

<do_one_initcall>:
e92d 41f0 stmdb sp!, {r4, r5, r6, r7, r8, lr}
ee1d 4f70 mrc 15, 0, r4, cr13, cr0, {3}
4606 mov r6, r0
b094 sub sp, #80 ; 0x50
f8d4 34e8 ldr.w r3, [r4, #1256] ; 0x4e8 <- stack canary
9313 str r3, [sp, #76] ; 0x4c
f8d4 8004 ldr.w r8, [r4, #4] <- preempt count

Co-developed-by: Keith Packard <keithpac@amazon.com>
Signed-off-by: Keith Packard <keithpac@amazon.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Amit Daniel Kachhap <amit.kachhap@arm.com>

gcc-plugins: arm-ssp: Prepare for THREAD_INFO_IN_TASK support

We will be enabling THREAD_INFO_IN_TASK support for ARM, which means
that we can no longer load the stack canary value by masking the stack
pointer and taking the copy that lives in thread_info. Instead, we will
be able to load it from the task_struct directly, by using the TPIDRURO
register which will hold the current task pointer when
THREAD_INFO_IN_TASK is in effect. This is much more straight-forward,
and allows us to declutter this code a bit while at it.

Note that this means that ARMv6 (non-v6K) SMP systems can no longer use
this feature, but those are quite rare to begin with, so this is a
reasonable trade off.

Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Amit Daniel Kachhap <amit.kachhap@arm.com>

irq: remove handle_domain_{irq,nmi}()

Now that entry code handles IRQ entry (including setting the IRQ regs)
before calling irqchip code, irqchip code can safely call
generic_handle_domain_irq(), and there's no functional reason for it to
call handle_domain_irq().

Let's cement this split of responsibility and remove handle_domain_irq()
entirely, updating irqchip drivers to call generic_handle_domain_irq().

For consistency, handle_domain_nmi() is similarly removed and replaced
with a generic_handle_domain_nmi() function which also does not perform
any entry logic.

Previously handle_domain_{irq,nmi}() had a WARN_ON() which would fire
when they were called in an inappropriate context. So that we can
identify similar issues going forward, similar WARN_ON_ONCE() logic is
added to the generic_handle_*() functions, and comments are updated for
clarity and consistency.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>

irq: arm: perform irqentry in entry code

In preparation for removing HANDLE_DOMAIN_IRQ_IRQENTRY, have arch/arm
perform all the irqentry accounting in its entry code.

For configurations with CONFIG_GENERIC_IRQ_MULTI_HANDLER, we can use
generic_handle_arch_irq(). Other than asm_do_IRQ(), all C calls to
handle_IRQ() are from irqchip handlers which will be called from
generic_handle_arch_irq(), so to avoid double accounting IRQ entry, the
entry logic is moved from handle_IRQ() into asm_do_IRQ().

For ARMv7M the entry assembly is tightly coupled with the NVIC irqchip, and
while the entry code should logically live under arch/arm/, moving the
entry logic there makes things more convoluted. So for now, place the
entry logic in the NVIC irqchip, but separated into a separate
function to make the split of responsibility clear.

For all other configurations without CONFIG_GENERIC_IRQ_MULTI_HANDLER,
IRQ entry is already handled in arch code, and requires no changes.

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com> # ARMv7M
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>

irq: add a (temporary) CONFIG_HANDLE_DOMAIN_IRQ_IRQENTRY

Going forward we want architecture/entry code to perform all the
necessary work to enter/exit IRQ context, with irqchip code merely
handling the mapping of the interrupt to any handler(s). Among other
reasons, this is necessary to consistently fix some longstanding issues
with the ordering of lockdep/RCU/tracing instrumentation which many
architectures get wrong today in their entry code.

Importantly, rcu_irq_{enter,exit}() must be called precisely once per
IRQ exception, so that rcu_is_cpu_rrupt_from_idle() can correctly
identify when an interrupt was taken from an idle context which must be
explicitly preempted. Currently handle_domain_irq() calls
rcu_irq_{enter,exit}() via irq_{enter,exit}(), but entry code needs to
be able to call rcu_irq_{enter,exit}() earlier for correct ordering
across lockdep/RCU/tracing updates for sequences such as:

lockdep_hardirqs_off(CALLER_ADDR0);
rcu_irq_enter();
trace_hardirqs_off_finish();

To permit each architecture to be converted to the new style in turn,
this patch adds a new CONFIG_HANDLE_DOMAIN_IRQ_IRQENTRY selected by all
current users of HANDLE_DOMAIN_IRQ, which gates the existing behaviour.
When CONFIG_HANDLE_DOMAIN_IRQ_IRQENTRY is not selected,
handle_domain_irq() requires entry code to perform the
irq_{enter,exit}() work, with an explicit check for this matching the
style of handle_domain_nmi().

Subsequent patches will:

1) Add the necessary IRQ entry accounting to each architecture in turn,
dropping CONFIG_HANDLE_DOMAIN_IRQ_IRQENTRY from that architecture's
Kconfig.

2) Remove CONFIG_HANDLE_DOMAIN_IRQ_IRQENTRY once it is no longer
selected.

3) Convert irqchip drivers to consistently use
generic_handle_domain_irq() rather than handle_domain_irq().

4) Remove handle_domain_irq() and CONFIG_HANDLE_DOMAIN_IRQ.

... which should leave us with a clear split of responsiblity across the
entry and irqchip code, making it possible to perform additional
cleanups and fixes for the aforementioned longstanding issues with entry
code.

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>

ARM: Recover kretprobe modified return address in stacktrace

Since the kretprobe replaces the function return address with
the kretprobe_trampoline on the stack, arm unwinder shows it
instead of the correct return address.

This finds the correct return address from the per-task
kretprobe_instances list and verify it is in between the
caller fp and callee fp.

Note that this supports both GCC and clang if CONFIG_FRAME_POINTER=y
and CONFIG_ARM_UNWIND=n. For the ARM unwinder, this is still
not working correctly.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

ARM: 9122/1: select HAVE_FUTEX_CMPXCHG

tglx notes:
This function [futex_detect_cmpxchg] is only needed when an
architecture has to runtime discover whether the CPU supports it or
not. ARM has unconditional support for this, so the obvious thing to
do is the below.

Fixes linkage failure from Clang randconfigs:
kernel/futex.o:(.text.fixup+0x5c): relocation truncated to fit: R_ARM_JUMP24 against `.init.text'
and boot failures for CONFIG_THUMB2_KERNEL.

Link: https://github.com/ClangBuiltLinux/linux/issues/325

Comments from Nick Desaulniers:

See-also: 03b8c7b623c8 ("futex: Allow architectures to skip
futex_atomic_cmpxchg_inatomic() test")

Reported-by: Arnd Bergmann <arnd@arndb.de>
Reported-by: Nathan Chancellor <nathan@kernel.org>
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Cc: stable@vger.kernel.org # v3.14+
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

firmware: include drivers/firmware/Kconfig unconditionally

Compile-testing drivers that require access to a firmware layer
fails when that firmware symbol is unavailable. This happened
twice this week:

- My proposed to change to rework the QCOM_SCM firmware symbol
broke on ppc64 and others.

- The cs_dsp firmware patch added device specific firmware loader
into drivers/firmware, which broke on the same set of
architectures.

We should probably do the same thing for other subsystems as well,
but fix this one first as this is a dependency for other patches
getting merged.

Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: Charles Keepax <ckeepax@opensource.cirrus.com>
Cc: Simon Trimmer <simont@opensource.cirrus.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: 9113/1: uaccess: remove set_fs() implementation

There are no remaining callers of set_fs(), so just remove it
along with all associated code that operates on
thread_info->addr_limit.

There are still further optimizations that can be done:

- In get_user(), the address check could be moved entirely
into the out of line code, rather than passing a constant
as an argument,

- I assume the DACR handling can be simplified as we now
only change it during user access when CONFIG_CPU_SW_DOMAIN_PAN
is set, but not during set_fs().

Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

tracing: Refactor TRACE_IRQFLAGS_SUPPORT in Kconfig

Make architectures select TRACE_IRQFLAGS_SUPPORT instead of
having many defines.

Link: https://lkml.kernel.org/r/20210731052233.4703-2-masahiroy@kernel.org

Acked-by: Heiko Carstens <hca@linux.ibm.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>   #arch/arc
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

ARM/nommu: use the generic dma-direct code for non-coherent devices

Select the right options to just use the generic dma-direct code
instead of reimplementing it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Dillon Min <dillon.minfei@gmail.com>

asm-generic: reverse GENERIC_{STRNCPY_FROM,STRNLEN}_USER symbols

Most architectures do not need a custom implementation, and in most
cases the generic implementation is preferred, so change the polariy
on these Kconfig symbols to require architectures to select them when
they provide their own version.

The new name is CONFIG_ARCH_HAS_{STRNCPY_FROM,STRNLEN}_USER.

The remaining architectures at the moment are: ia64, mips, parisc,
um and xtensa. We should probably convert these as well, but
I was not sure how far to take this series. Thomas Bogendoerfer
had some concerns about converting mips but may still do some
more detailed measurements to see which version is better.

Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: linux-ia64@vger.kernel.org
Cc: linux-mips@vger.kernel.org
Cc: linux-parisc@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linux-um@lists.infradead.org
Cc: linux-xtensa@linux-xtensa.org
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Helge Deller <deller@gmx.de> # parisc
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

arch: Kconfig: clean up obsolete use of HAVE_IDE

The arch-specific Kconfig files use HAVE_IDE to indicate if IDE is
supported.

As IDE support and the HAVE_IDE config vanishes with commit b7fb14d3ac63
("ide: remove the legacy ide driver"), there is no need to mention
HAVE_IDE in all those arch-specific Kconfig files.

The issue was identified with ./scripts/checkkconfigsymbols.py.

Fixes: b7fb14d3ac63 ("ide: remove the legacy ide driver")
Suggested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20210728182115.4401-1-lukas.bulwahn@gmail.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

arm: Typo s/PCI_IXP4XX_LEGACY/IXP4XX_PCI_LEGACY/

Kconfig symbol PCI_IXP4XX_LEGACY does not exist, but IXP4XX_PCI_LEGACY
does.

Fixes: d5d9f7ac58ea1041 ("ARM/ixp4xx: Make NEED_MACH_IO_H optional")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/82ce37c617293521f095a945a255456b9512769c.1626255077.git.geert+renesas@glider.be'
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM/ixp4xx: Make NEED_MACH_IO_H optional

In order to create a proper PCI driver for the IXP4xx
we need to make the old PCI driver and its reliance
on <mach/io.h> optional.

Create a new Kconfig symbol for the legacy PCI driver
IXP4XX_PCI_LEGACY and only activate NEED_MACH_IO_H
for this driver.

A few files need to be adjusted to explicitly include
the <mach/hardware.h> and <mach/cpu.h> headers that
they previously obtained implicitly using <linux/io.h>
that would include <mach/io.h> and in turn include
these two headers.

This breaks our reliance on the old PCI and indirect
PCI support so we can reimplement a proper purely
DT-based driver in the PCI subsystem.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Imre Kaloz <kaloz@openwrt.org>
Cc: Krzysztof Halasa <khalasa@piap.pl>
Cc: Zoltan HERPAI <wigyori@uid0.hu>
Cc: Raylynn Knight <rayknight@me.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

mm: generalize ZONE_[DMA|DMA32]

ZONE_[DMA|DMA32] configs have duplicate definitions on platforms that
subscribe to them. Instead, just make them generic options which can be
selected on applicable platforms.

Also only x86/arm64 architectures could enable both ZONE_DMA and
ZONE_DMA32 if EXPERT, add ARCH_HAS_ZONE_DMA_SET to make dma zone
configurable and visible on the two architectures.

Link: https://lkml.kernel.org/r/20210528074557.17768-1-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com> [arm64]
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> [m68k]
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Palmer Dabbelt <palmerdabbelt@google.com> [RISC-V]
Acked-by: Michal Simek <michal.simek@xilinx.com> [microblaze]
Acked-by: Michael Ellerman <mpe@ellerman.id.au> [powerpc]
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <linux@armlinux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

clkdev: remove CONFIG_CLKDEV_LOOKUP

This option is now synonymous with CONFIG_HAVE_CLK, so use
the latter globally. Any out-of-tree platform ports that
still use a private clk_get()/clk_put() implementation should
move to CONFIG_COMMON_CLK.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

locking/atomic: delete !ARCH_ATOMIC remnants

Now that all architectures implement ARCH_ATOMIC, we can make it
mandatory, removing the Kconfig symbol and logic for !ARCH_ATOMIC.

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210525140232.53872-33-mark.rutland@arm.com

locking/atomic: arm: move to ARCH_ATOMIC

We'd like all architectures to convert to ARCH_ATOMIC, as once all
architectures are converted it will be possible to make significant
cleanups to the atomics headers, and this will make it much easier to
generically enable atomic functionality (e.g. debug logic in the
instrumented wrappers).

As a step towards that, this patch migrates alpha to ARCH_ATOMIC. The
arch code provides arch_{atomic,atomic64,xchg,cmpxchg}*(), and common
code wraps these with optional instrumentation to provide the regular
functions.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210525140232.53872-16-mark.rutland@arm.com

mm: drop redundant HAVE_ARCH_TRANSPARENT_HUGEPAGE

HAVE_ARCH_TRANSPARENT_HUGEPAGE has duplicate definitions on platforms
that subscribe it. Drop these reduntant definitions and instead just
select it on applicable platforms.

Link: https://lkml.kernel.org/r/1617259448-22529-7-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Vineet Gupta <vgupta@synopsys.com> [arc]
Cc: Russell King <linux@armlinux.org.uk>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Palmer Dabbelt <palmerdabbelt@google.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Rich Felker <dalias@libc.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm: generalize SYS_SUPPORTS_HUGETLBFS (rename as ARCH_SUPPORTS_HUGETLBFS)

SYS_SUPPORTS_HUGETLBFS config has duplicate definitions on platforms
that subscribe it. Instead, just make it a generic option which can be
selected on applicable platforms.

Also rename it as ARCH_SUPPORTS_HUGETLBFS instead. This reduces code
duplication and makes it cleaner.

Link: https://lkml.kernel.org/r/1617259448-22529-3-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com> [arm64]
Acked-by: Palmer Dabbelt <palmerdabbelt@google.com> [riscv]
Acked-by: Michael Ellerman <mpe@ellerman.id.au> [powerpc]
Cc: Russell King <linux@armlinux.org.uk>
Cc: Will Deacon <will@kernel.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/memtest: add ARCH_USE_MEMTEST

early_memtest() does not get called from all architectures. Hence
enabling CONFIG_MEMTEST and providing a valid memtest=[1..N] kernel
command line option might not trigger the memory pattern tests as would be
expected in normal circumstances. This situation is misleading.

The change here prevents the above mentioned problem after introducing a
new config option ARCH_USE_MEMTEST that should be subscribed on platforms
that call early_memtest(), in order to enable the config CONFIG_MEMTEST.
Conversely CONFIG_MEMTEST cannot be enabled on platforms where it would
not be tested anyway.

Link: https://lkml.kernel.org/r/1617269193-22294-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com> (arm64)
Reviewed-by: Max Filippov <jcmvbkbc@gmail.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Will Deacon <will@kernel.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Chris Zankel <chris@zankel.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ARM: socfpga: introduce common ARCH_INTEL_SOCFPGA

Simplify 32-bit and 64-bit Intel SoCFPGA Kconfig options by having only
one for both of them. This the common practice for other platforms.
Additionally, the ARCH_SOCFPGA is too generic as SoCFPGA designs come
from multiple vendors.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>

ARM: 9063/1: mm: reduce maximum number of CPUs if DEBUG_KMAP_LOCAL is enabled

The debugging code for kmap_local() doubles the number of per-CPU fixmap
slots allocated for kmap_local(), in order to use half of them as guard
regions. This causes the fixmap region to grow downwards beyond the start
of its reserved window if the supported number of CPUs is large, and collide
with the newly added virtual DT mapping right below it, which is obviously
not good.

One manifestation of this is EFI boot on a kernel built with NR_CPUS=32
and CONFIG_DEBUG_KMAP_LOCAL=y, which may pass the FDT in highmem, resulting
in block entries below the fixmap region that the fixmap code misidentifies
as fixmap table entries, and subsequently tries to dereference using a
phys-to-virt translation that is only valid for lowmem. This results in a
cryptic splat such as the one below.

ftrace: allocating 45548 entries in 89 pages
8<--- cut here ---
Unable to handle kernel paging request at virtual address fc6006f0
pgd = (ptrval)
[fc6006f0] *pgd=80000040207003, *pmd=00000000
Internal error: Oops: a06 [#1] SMP ARM
Modules linked in:
CPU: 0 PID: 0 Comm: swapper Not tainted 5.11.0+ #382
Hardware name: Generic DT based system
PC is at cpu_ca15_set_pte_ext+0x24/0x30
LR is at __set_fixmap+0xe4/0x118
pc : [<c041ac9c>] lr : [<c04189d8>] psr: 400000d3
sp : c1601ed8 ip : 00400000 fp : 00800000
r10: 0000071f r9 : 00421000 r8 : 00c00000
r7 : 00c00000 r6 : 0000071f r5 : ffade000 r4 : 4040171f
r3 : 00c00000 r2 : 4040171f r1 : c041ac78 r0 : fc6006f0
Flags: nZcv IRQs off FIQs off Mode SVC_32 ISA ARM Segment none
Control: 30c5387d Table: 40203000 DAC: 00000001
Process swapper (pid: 0, stack limit = 0x(ptrval))

So let's limit CONFIG_NR_CPUS to 16 when CONFIG_DEBUG_KMAP_LOCAL=y. Also,
fix the BUILD_BUG_ON() check that was supposed to catch this, by checking
whether the region grows below the start address rather than above the end
address.

Fixes: 2a15ba82fa6ca3f3 ("ARM: highmem: Switch to generic kmap atomic")
Reported-by: Peter Robinson <pbrobinson@gmail.com>
Tested-by: Peter Robinson <pbrobinson@gmail.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

ARM: ep93xx: Select GENERIC_IRQ_MULTI_HANDLER directly

ep93xx currently relies of CONFIG_ARM_VIC to select
GENERIC_IRQ_MULTI_HANDLER. Given that this is logically a platform
architecture property, add the selection of GENERIC_IRQ_MULTI_HANDLER
at the platform level.

Further patches will remove the selection from the irqchip side.

Reported-by: Marc Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Hector Martin <marcan@marcan.st>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>

ARM: 9050/1: Kconfig: Select ARCH_HAVE_NMI_SAFE_CMPXCHG where possible

Currently ARCH_HAVE_NMI_SAFE_CMPXCHG is not set on Arm systems and this
makes it impossible to enable features such as ftrace histogram triggers
on Arm platforms.

Most Arm systems are NMI safe simply because there is no NMI but this isn't
universally true meaning we cannot set ARCH_HAVE_NMI_SAFE_CMPXCHG for all
Arm devices. However the load/store exclusive implementation of cmpxchg is
NMI-safe and this implementation is used ARMv6k and later. Let's select
ARCH_HAVE_NMI_SAFE_CMPXCHG for these systems.

Note that ARMv6 uses load/store exclusive for 32-bit cmpxchg but relies on
interrupt masking for 8- and 16-bit operations. This patch is conservative
and does not change behaviour for CPU_V6.

Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

ARM: 9045/1: uncompress: Validate start of physical memory against passed DTB

Currently, the start address of physical memory is obtained by masking
the program counter with a fixed mask of 0xf8000000. This mask value
was chosen as a balance between the requirements of different platforms.
However, this does require that the start address of physical memory is
a multiple of 128 MiB, precluding booting Linux on platforms where this
requirement is not fulfilled.

Fix this limitation by validating the masked address against the memory
information in the passed DTB. Only use the start address
from DTB when masking would yield an out-of-range address, prefer the
traditional method in all other cases. Note that this applies only to the
explicitly passed DTB on modern systems, and not to a DTB appended to
the kernel, or to ATAGS. The appended DTB may need to be augmented by
information from ATAGS, which may need to rely on knowledge of the start
address of physical memory itself.

This allows to boot Linux on r7s9210/rza2mevb using the 64 MiB of SDRAM
on the RZA2MEVB sub board, which is located at 0x0C000000 (CS3 space),
i.e. not at a multiple of 128 MiB.

Suggested-by: Nicolas Pitre <nico@fluxnic.net>
Suggested-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

arch: arm: Remove CONFIG_OPROFILE support

The "oprofile" user-space tools don't use the kernel OPROFILE support
any more, and haven't in a long time. User-space has been converted to
the perf interfaces.

Remove the old oprofile's architecture specific support.

Suggested-by: Christoph Hellwig <hch@infradead.org>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Robert Richter <rric@kernel.org>
Acked-by: William Cohen <wcohen@redhat.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Thomas Gleixner <tglx@linutronix.de>

ARM: remove u300 platform

The Ericsson U300 platform was one of two ARM929 based SoC platforms for
mobile phones in ST-Ericsson after the merger of Ericsson with ST-NXP
into ST-Ericsson, the other one being the ST Nomadik.

The platform was not widely adopted in Linux based systems and was
replaced with the far superior ST-Ericsson U8500 in 2011, but Linus
Walleij kept maintaining the code for the whole time.

Linus continues to use the Nomadik machine, but decided to drop
u300 from the kernel as part of this year's spring cleaning.
Thanks for having maintained it all these years.

Cc: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/lkml/CACRpkdbJkiHR9FSfJTH_5d_qRU1__dRXHM1TL40iqNRKbGQfrQ@mail.gmail.com/
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: remove tango platform

The smp8758 (tango4) SoC was the last generation of set-top-box chips
to come out of Sigma Designs, and support was added by Marc Gonzalez
and Måns Rullgård between 2015 and 2017, before the company went out of
business and the products were abandoned.

The chip is used in some set-top-boxes such as the Popcorn Hour A-500,
which could have seen some adoption by hobbyists. This has not happened
in the past four years, and support for the more widely used MIPS based
SoCs was never merged at all.

Thanks to Marc and Måns for maintaining for the past years even after the
death of the platform.

Cc: Marc Gonzalez <marc.w.gonzalez@free.fr>
Cc: Mans Rullgard <mans@mansr.com>
Link: https://lore.kernel.org/lkml/2d643ebc-09af-a809-eb3f-2aec8ecee501@free.fr/
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: remove zte zx platform

The ZTE ZX set-top-box SoC platform was added in 2015 by Jun Nie, with
Baoyou Xie and Shawn Guo subsequently becoming maintainers after the
addition of the 64-bit variant.

However, the only machines that were ever supported upstream are the
reference designs, not actual set-top-box devices that would benefit
from this support. All ZTE set-top-boxes from the past few years seem
to be based on third-party SoCs. While there is very little information
about zx296702 and zx296718 on the web, I found some references to other
chips from the same family, such as zx296716 and zx296719, which were
never submitted for upstream support. Finally, there is no support for
the GPU on either of them, with the lima and panfrost device drivers
having been added after work on the zx platform had stopped.

Shawn confirmed that he has not seen any interest in this platform for
the past four years, and that it can be removed.

Thanks to Jun and Shawn for maintaining this platform over the past
five years.

Cc: Jun Nie <jun.nie@linaro.org>
Cc: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: remove sirf prima2/atlas platforms

The SiRF Prima2 and Atlas platform code was contributed by Cambridge
Silicon Radio (CSR) after aquiring the original SiRF company, and
maintained by Barry Song. CSR was subsequently acquired by Qualcomm,
who no longer have an interest in maintaining the SoC platform but
instead have released more recent SoCs for the same market in the
Snapdragon family.

As Barry is no longer working for the company, nobody else there
wants to maintain it, and there are no third-party users, the
best way forward seems to be to completely remove it.

Thanks to Barry for maintaining the platform for the past ten years.

Cc: Barry Song <baohua@kernel.org>
Link: https://lore.kernel.org/lkml/c969392572604b98bcb3be44048c3165@hisilicon.com/
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: drop efm32 platform

I didn't touch this code since it served as a platform to introduce
ARMv7-M support to Linux. The only known machine that runs Linux has only
4 MiB of RAM (that originally only exists to hold the display's framebuffer).

There are no known users and no further use foreseeable, so drop the
code.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20210115155130.185010-2-u.kleine-koenig@pengutronix.de'
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: Remove PicoXcell platform support

PicoXcell has had nothing but treewide cleanups for at least the last 8
years and no signs of activity. The most recent activity is a yocto vendor
kernel based on v3.0 in 2015.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Jamie Iles <jamie@jamieiles.com>
Cc: Russell King <linux@armlinux.org.uk>
Link: https://lore.kernel.org/r/20201210200315.2965567-3-robh@kernel.org'
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

arm, arm64: move free_unused_memmap() to generic mm

ARM and ARM64 free unused parts of the memory map just before the
initialization of the page allocator. To allow holes in the memory map both
architectures overload pfn_valid() and define HAVE_ARCH_PFN_VALID.

Allowing holes in the memory map for FLATMEM may be useful for small
machines, such as ARC and m68k and will enable those architectures to cease
using DISCONTIGMEM and still support more than one memory bank.

Move the functions that free unused memory map to generic mm and enable
them in case HAVE_ARCH_PFN_VALID=y.

Link: https://lkml.kernel.org/r/20201101170454.9567-10-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com> [arm64]
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Meelis Roos <mroos@linux.ee>
Cc: Michael Schmitz <schmitzmic@gmail.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arm: remove CONFIG_ARCH_HAS_HOLES_MEMORYMODEL

ARM is the only architecture that defines CONFIG_ARCH_HAS_HOLES_MEMORYMODEL
which in turn enables memmap_valid_within() function that is intended to
verify existence of struct page associated with a pfn when there are holes
in the memory map.

However, the ARCH_HAS_HOLES_MEMORYMODEL also enables HAVE_ARCH_PFN_VALID
and arch-specific pfn_valid() implementation that also deals with the holes
in the memory map.

The only two users of memmap_valid_within() call this function after
a call to pfn_valid() so the memmap_valid_within() check becomes redundant.

Remove CONFIG_ARCH_HAS_HOLES_MEMORYMODEL and memmap_valid_within() and rely
entirely on ARM's implementation of pfn_valid() that is now enabled
unconditionally.

Link: https://lkml.kernel.org/r/20201101170454.9567-9-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Meelis Roos <mroos@linux.ee>
Cc: Michael Schmitz <schmitzmic@gmail.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arm: Use the generic devmem_is_allowed()

This is exactly the same as the arm64 version, which I recently copied
into lib/ for use by the RISC-V port.

Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

kbuild: Hoist '--orphan-handling' into Kconfig

Currently, '--orphan-handling=warn' is spread out across four different
architectures in their respective Makefiles, which makes it a little
unruly to deal with in case it needs to be disabled for a specific
linker version (in this case, ld.lld 10.0.1).

To make it easier to control this, hoist this warning into Kconfig and
the main Makefile so that disabling it is simpler, as the warning will
only be enabled in a couple places (main Makefile and a couple of
compressed boot folders that blow away LDFLAGS_vmlinx) and making it
conditional is easier due to Kconfig syntax. One small additional
benefit of this is saving a call to ld-option on incremental builds
because we will have already evaluated it for CONFIG_LD_ORPHAN_WARN.

To keep the list of supported architectures the same, introduce
CONFIG_ARCH_WANT_LD_ORPHAN_WARN, which an architecture can select to
gain this automatically after all of the sections are specified and size
asserted. A special thanks to Kees Cook for the help text on this
config.

Link: https://github.com/ClangBuiltLinux/linux/issues/1187
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

ARM: highmem: Switch to generic kmap atomic

No reason having the same code in every architecture.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20201103095857.582196476@linutronix.de

timekeeping: default GENERIC_CLOCKEVENTS to enabled

Almost all machines use GENERIC_CLOCKEVENTS, so it feels wrong to
require each one to select that symbol manually.

Instead, enable it whenever CONFIG_LEGACY_TIMER_TICK is disabled as
a simplification. It should be possible to select both
GENERIC_CLOCKEVENTS and LEGACY_TIMER_TICK from an architecture now
and decide at runtime between the two.

For the clockevents arch-support.txt file, this means that additional
architectures are marked as TODO when they have at least one machine
that still uses LEGACY_TIMER_TICK, rather than being marked 'ok' when
at least one machine has been converted. This means that both m68k and
arm (for riscpc) revert to TODO.

At this point, we could just always enable CONFIG_GENERIC_CLOCKEVENTS
rather than leaving it off when not needed. I built an m68k
defconfig kernel (using gcc-10.1.0) and found that this would add
around 5.5KB in kernel image size:

text data bss dec hex filename
3861936 1092236 196656 5150828 4e986c obj-m68k/vmlinux-no-clockevent
3866201 1093832 196184 5156217 4ead79 obj-m68k/vmlinux-clockevent

On Arm (MACH_RPC), that difference appears to be twice as large,
around 11KB on top of an 6MB vmlinux.

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: rpc: use legacy_timer_tick

rpc is the only user of the timer_tick() function now, and can
just call the newly added generic version instead.

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: remove ebsa110 platform

Russell said that he is no longer using this machine, and it seems that
nobody else has in a long time, so it's time to say goodbye to it.

As this is the last platform using CONFIG_ARCH_USES_GETTIMEOFFSET,
there are some follow-up patches to remove that as well.

Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: p2v: reduce p2v alignment requirement to 2 MiB

The ARM kernel's linear map starts at PAGE_OFFSET, which maps to a
physical address (PHYS_OFFSET) that is platform specific, and is
discovered at boot. Since we don't want to slow down translations
between physical and virtual addresses by keeping the offset in a
variable in memory, we implement this by patching the code performing
the translation, and putting the offset between PAGE_OFFSET and the
start of physical RAM directly into the instruction opcodes.

As we only patch up to 8 bits of offset, yielding 4 GiB >> 8 == 16 MiB
of granularity, we have to round up PHYS_OFFSET to the next multiple if
the start of physical RAM is not a multiple of 16 MiB. This wastes some
physical RAM, since the memory that was skipped will now live below
PAGE_OFFSET, making it inaccessible to the kernel.

We can improve this by changing the patchable sequences and the patching
logic to carry more bits of offset: 11 bits gives us 4 GiB >> 11 == 2 MiB
of granularity, and so we will never waste more than that amount by
rounding up the physical start of DRAM to the next multiple of 2 MiB.
(Note that 2 MiB granularity guarantees that the linear mapping can be
created efficiently, whereas less than 2 MiB may result in the linear
mapping needing another level of page tables)

This helps Zhen Lei's scenario, where the start of DRAM is known to be
occupied. It also helps EFI boot, which relies on the firmware's page
allocator to allocate space for the decompressed kernel as low as
possible. And if the KASLR patches ever land for 32-bit, it will give
us 3 more bits of randomization of the placement of the kernel inside
the linear region.

For the ARM code path, it simply comes down to using two add/sub
instructions instead of one for the carryless version, and patching
each of them with the correct immediate depending on the rotation
field. For the LPAE calculation, which has to deal with a carry, it
patches the MOVW instruction with up to 12 bits of offset (but we only
need 11 bits anyway)

For the Thumb2 code path, patching more than 11 bits of displacement
would be somewhat cumbersome, but the 11 bits we need fit nicely into
the second word of the u16[2] opcode, so we simply update the immediate
assignment and the left shift to create an addend of the right magnitude.

Suggested-by: Zhen Lei <thunder.leizhen@huawei.com>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

ARM: 9017/2: Enable KASan for ARM

This patch enables the kernel address sanitizer for ARM. XIP_KERNEL
has not been tested and is therefore not allowed for now.

Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: kasan-dev@googlegroups.com
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Ard Biesheuvel <ardb@kernel.org> # QEMU/KVM/mach-virt/LPAE/8G
Tested-by: Florian Fainelli <f.fainelli@gmail.com> # Brahma SoCs
Tested-by: Ahmad Fatoum <a.fatoum@pengutronix.de> # i.MX6Q
Signed-off-by: Abbott Liu <liuwenliang@huawei.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

ARM: 9015/2: Define the virtual space of KASan's shadow region

Define KASAN_SHADOW_OFFSET,KASAN_SHADOW_START and KASAN_SHADOW_END for
the Arm kernel address sanitizer. We are "stealing" lowmem (the 4GB
addressable by a 32bit architecture) out of the virtual address
space to use as shadow memory for KASan as follows:

+----+ 0xffffffff
| |
| | |-> Static kernel image (vmlinux) BSS and page table
| |/
+----+ PAGE_OFFSET
| |
| | |-> Loadable kernel modules virtual address space area
| |/
+----+ MODULES_VADDR = KASAN_SHADOW_END
| |
| | |-> The shadow area of kernel virtual address.
| |/
+----+-> TASK_SIZE (start of kernel space) = KASAN_SHADOW_START the
| | shadow address of MODULES_VADDR
| | |
| | |
| | |-> The user space area in lowmem. The kernel address
| | | sanitizer do not use this space, nor does it map it.
| | |
| | |
| | |
| | |
| |/
------ 0

0 .. TASK_SIZE is the memory that can be used by shared
userspace/kernelspace. It us used for userspace processes and for
passing parameters and memory buffers in system calls etc. We do not
need to shadow this area.

KASAN_SHADOW_START:
This value begins with the MODULE_VADDR's shadow address. It is the
start of kernel virtual space. Since we have modules to load, we need
to cover also that area with shadow memory so we can find memory
bugs in modules.

KASAN_SHADOW_END
This value is the 0x100000000's shadow address: the mapping that would
be after the end of the kernel memory at 0xffffffff. It is the end of
kernel address sanitizer shadow area. It is also the start of the
module area.

KASAN_SHADOW_OFFSET:
This value is used to map an address to the corresponding shadow
address by the following formula:

shadow_addr = (address >> 3) + KASAN_SHADOW_OFFSET;

As you would expect, >> 3 is equal to dividing by 8, meaning each
byte in the shadow memory covers 8 bytes of kernel memory, so one
bit shadow memory per byte of kernel memory is used.

The KASAN_SHADOW_OFFSET is provided in a Kconfig option depending
on the VMSPLIT layout of the system: the kernel and userspace can
split up lowmem in different ways according to needs, so we calculate
the shadow offset depending on this.

When kasan is enabled, the definition of TASK_SIZE is not an 8-bit
rotated constant, so we need to modify the TASK_SIZE access code in the
*.s file.

The kernel and modules may use different amounts of memory,
according to the VMSPLIT configuration, which in turn
determines the PAGE_OFFSET.

We use the following KASAN_SHADOW_OFFSETs depending on how the
virtual memory is split up:

- 0x1f000000 if we have 1G userspace / 3G kernelspace split:
- The kernel address space is 3G (0xc0000000)
- PAGE_OFFSET is then set to 0x40000000 so the kernel static
image (vmlinux) uses addresses 0x40000000 .. 0xffffffff
- On top of that we have the MODULES_VADDR which under
the worst case (using ARM instructions) is
PAGE_OFFSET - 16M (0x01000000) = 0x3f000000
so the modules use addresses 0x3f000000 .. 0x3fffffff
- So the addresses 0x3f000000 .. 0xffffffff need to be
covered with shadow memory. That is 0xc1000000 bytes
of memory.
- 1/8 of that is needed for its shadow memory, so
0x18200000 bytes of shadow memory is needed. We
"steal" that from the remaining lowmem.
- The KASAN_SHADOW_START becomes 0x26e00000, to
KASAN_SHADOW_END at 0x3effffff.
- Now we can calculate the KASAN_SHADOW_OFFSET for any
kernel address as 0x3f000000 needs to map to the first
byte of shadow memory and 0xffffffff needs to map to
the last byte of shadow memory. Since:
SHADOW_ADDR = (address >> 3) + KASAN_SHADOW_OFFSET
0x26e00000 = (0x3f000000 >> 3) + KASAN_SHADOW_OFFSET
KASAN_SHADOW_OFFSET = 0x26e00000 - (0x3f000000 >> 3)
KASAN_SHADOW_OFFSET = 0x26e00000 - 0x07e00000
KASAN_SHADOW_OFFSET = 0x1f000000

- 0x5f000000 if we have 2G userspace / 2G kernelspace split:
- The kernel space is 2G (0x80000000)
- PAGE_OFFSET is set to 0x80000000 so the kernel static
image uses 0x80000000 .. 0xffffffff.
- On top of that we have the MODULES_VADDR which under
the worst case (using ARM instructions) is
PAGE_OFFSET - 16M (0x01000000) = 0x7f000000
so the modules use addresses 0x7f000000 .. 0x7fffffff
- So the addresses 0x7f000000 .. 0xffffffff need to be
covered with shadow memory. That is 0x81000000 bytes
of memory.
- 1/8 of that is needed for its shadow memory, so
0x10200000 bytes of shadow memory is needed. We
"steal" that from the remaining lowmem.
- The KASAN_SHADOW_START becomes 0x6ee00000, to
KASAN_SHADOW_END at 0x7effffff.
- Now we can calculate the KASAN_SHADOW_OFFSET for any
kernel address as 0x7f000000 needs to map to the first
byte of shadow memory and 0xffffffff needs to map to
the last byte of shadow memory. Since:
SHADOW_ADDR = (address >> 3) + KASAN_SHADOW_OFFSET
0x6ee00000 = (0x7f000000 >> 3) + KASAN_SHADOW_OFFSET
KASAN_SHADOW_OFFSET = 0x6ee00000 - (0x7f000000 >> 3)
KASAN_SHADOW_OFFSET = 0x6ee00000 - 0x0fe00000
KASAN_SHADOW_OFFSET = 0x5f000000

- 0x9f000000 if we have 3G userspace / 1G kernelspace split,
and this is the default split for ARM:
- The kernel address space is 1GB (0x40000000)
- PAGE_OFFSET is set to 0xc0000000 so the kernel static
image uses 0xc0000000 .. 0xffffffff.
- On top of that we have the MODULES_VADDR which under
the worst case (using ARM instructions) is
PAGE_OFFSET - 16M (0x01000000) = 0xbf000000
so the modules use addresses 0xbf000000 .. 0xbfffffff
- So the addresses 0xbf000000 .. 0xffffffff need to be
covered with shadow memory. That is 0x41000000 bytes
of memory.
- 1/8 of that is needed for its shadow memory, so
0x08200000 bytes of shadow memory is needed. We
"steal" that from the remaining lowmem.
- The KASAN_SHADOW_START becomes 0xb6e00000, to
KASAN_SHADOW_END at 0xbfffffff.
- Now we can calculate the KASAN_SHADOW_OFFSET for any
kernel address as 0xbf000000 needs to map to the first
byte of shadow memory and 0xffffffff needs to map to
the last byte of shadow memory. Since:
SHADOW_ADDR = (address >> 3) + KASAN_SHADOW_OFFSET
0xb6e00000 = (0xbf000000 >> 3) + KASAN_SHADOW_OFFSET
KASAN_SHADOW_OFFSET = 0xb6e00000 - (0xbf000000 >> 3)
KASAN_SHADOW_OFFSET = 0xb6e00000 - 0x17e00000
KASAN_SHADOW_OFFSET = 0x9f000000

- 0x8f000000 if we have 3G userspace / 1G kernelspace with
full 1 GB low memory (VMSPLIT_3G_OPT):
- The kernel address space is 1GB (0x40000000)
- PAGE_OFFSET is set to 0xb0000000 so the kernel static
image uses 0xb0000000 .. 0xffffffff.
- On top of that we have the MODULES_VADDR which under
the worst case (using ARM instructions) is
PAGE_OFFSET - 16M (0x01000000) = 0xaf000000
so the modules use addresses 0xaf000000 .. 0xaffffff
- So the addresses 0xaf000000 .. 0xffffffff need to be
covered with shadow memory. That is 0x51000000 bytes
of memory.
- 1/8 of that is needed for its shadow memory, so
0x0a200000 bytes of shadow memory is needed. We
"steal" that from the remaining lowmem.
- The KASAN_SHADOW_START becomes 0xa4e00000, to
KASAN_SHADOW_END at 0xaeffffff.
- Now we can calculate the KASAN_SHADOW_OFFSET for any
kernel address as 0xaf000000 needs to map to the first
byte of shadow memory and 0xffffffff needs to map to
the last byte of shadow memory. Since:
SHADOW_ADDR = (address >> 3) + KASAN_SHADOW_OFFSET
0xa4e00000 = (0xaf000000 >> 3) + KASAN_SHADOW_OFFSET
KASAN_SHADOW_OFFSET = 0xa4e00000 - (0xaf000000 >> 3)
KASAN_SHADOW_OFFSET = 0xa4e00000 - 0x15e00000
KASAN_SHADOW_OFFSET = 0x8f000000

- The default value of 0xffffffff for KASAN_SHADOW_OFFSET
is an error value. We should always match one of the
above shadow offsets.

When we do this, TASK_SIZE will sometimes get a bit odd values
that will not fit into immediate mov assembly instructions.
To account for this, we need to rewrite some assembly using
TASK_SIZE like this:

- mov r1, #TASK_SIZE
+ ldr r1, =TASK_SIZE

or

- cmp r4, #TASK_SIZE
+ ldr r0, =TASK_SIZE
+ cmp r4, r0

this is done to avoid the immediate #TASK_SIZE that need to
fit into a limited number of bits.

Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: kasan-dev@googlegroups.com
Cc: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Ard Biesheuvel <ardb@kernel.org> # QEMU/KVM/mach-virt/LPAE/8G
Tested-by: Florian Fainelli <f.fainelli@gmail.com> # Brahma SoCs
Tested-by: Ahmad Fatoum <a.fatoum@pengutronix.de> # i.MX6Q
Reported-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Abbott Liu <liuwenliang@huawei.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

Partially revert "ARM: 8905/1: Emit __gnu_mcount_nc when using Clang 10.0.0 or newer"

This partially reverts commit b0fe66cf095016e0b238374c10ae366e1f087d11.

The minimum supported version of clang is now clang 10.0.1. We still
want to pass -meabi=gnu.

Suggested-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Fangrui Song <maskray@google.com>
Cc: Marco Elver <elver@google.com>
Cc: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lkml.kernel.org/r/20200902225911.209899-6-ndesaulniers@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

seccomp: Move config option SECCOMP to arch/Kconfig

In order to make adding configurable features into seccomp easier,
it's better to have the options at one single location, considering
especially that the bulk of seccomp code is arch-independent. An quick
look also show that many SECCOMP descriptions are outdated; they talk
about /proc rather than prctl.

As a result of moving the config option and keeping it default on,
architectures arm, arm64, csky, riscv, sh, and xtensa did not have SECCOMP
on by default prior to this and SECCOMP will be default in this change.

Architectures microblaze, mips, powerpc, s390, sh, and sparc have an
outdated depend on PROC_FS and this dependency is removed in this change.

Suggested-by: Jann Horn <jannh@google.com>
Link: https://lore.kernel.org/lkml/CAG48ez1YWz9cnp08UZgeieYRhHdqh-ch7aNwc4JRBnGyrmgfMg@mail.gmail.com/
Signed-off-by: YiFei Zhu <yifeifz2@illinois.edu>
[kees: added HAVE_ARCH_SECCOMP help text, tweaked wording]
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/9ede6ef35c847e58d61e476c6a39540520066613.1600951211.git.yifeifz2@illinois.edu

ARM: Allow IPIs to be handled as normal interrupts

In order to deal with IPIs as normal interrupts, let's add
a new way to register them with the architecture code.

set_smp_ipi_range() takes a range of interrupts, and allows
the arch code to request them as if the were normal interrupts.
A standard handler is then called by the core IRQ code to deal
with the IPI.

This means that we don't need to call irq_enter/irq_exit, and
that we don't need to deal with set_irq_regs either. So let's
move the dispatcher into its own function, and leave handle_IPI()
as a compatibility function.

On the sending side, let's make use of ipi_send_mask, which
already exists for this purpose.

One of the major difference is that we end up, in some cases
(such as when performing IRQ time accounting on the scheduler
IPI), end up with nested irq_enter()/irq_exit() pairs.
Other than the (relatively small) overhead, there should be
no consequences to it (these pairs are designed to nest
correctly, and the accounting shouldn't be off).

Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>

uaccess: add infrastructure for kernel builds with set_fs()

Add a CONFIG_SET_FS option that is selected by architecturess that
implement set_fs, which is all of them initially. If the option is not
set stubs for routines related to overriding the address space are
provided so that architectures can start to opt out of providing set_fs.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

ARM: versatile: Remove Integrator and Realview from PHYS_OFFSET

Both Integrator and Realview exclusively use
ARM_PATCH_PHYS_VIRT these days so drop them from the
PHYS_OFFSET Kconfig option.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20200814154529.3487163-1-linus.walleij@linaro.org

ARM: s3c: move into a common directory

s3c24xx and s3c64xx have a lot in common, but are split across three
separate directories, which makes the interaction of the header files
more complicated than necessary.

Move all three directories into a new mach-s3c, with a minimal
set of changes to each file.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
[krzk: Rebase, add s3c24xx and s3c64xx suffix to several files, add SPDX
headers to new files, remove plat-samsung from MAINTAINERS]
Co-developed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
https://lore.kernel.org/r/20200806182059.2431-39-krzk@kernel.org

ARM: s3c24xx: fix missing system reset

Commit f6361c6b3880 ("ARM: S3C24XX: remove separate restart code")
removed usage of the watchdog reset platform code in favor of the
Samsung SoC watchdog driver. However the latter was not selected thus
S3C24xx platforms lost reset abilities.

Cc: <stable@vger.kernel.org>
Fixes: f6361c6b3880 ("ARM: S3C24XX: remove separate restart code")
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>

ARM: samsung: remove HAVE_S3C2410_WATCHDOG and use direct dependencies

A separate Kconfig option HAVE_S3C2410_WATCHDOG for Samsung SoCs is not
really needed and the s3c24xx watchdog driver can depend on Samsung ARM
architectures instead.

The "HAVE_xxx_WATCHDOG" pattern of dependency is not popular and Samsung
platforms are here exceptions. All others just depend on
CONFIG_ARCH_xxx.

This makes the code slightly smaller without any change in
functionality.

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Guenter Roeck <linux@roeck-us.net>

arm, arm64: Fix selection of CONFIG_SCHED_THERMAL_PRESSURE

Qian reported that the current setup forgoes the Kconfig dependencies and
results in warnings such as:

WARNING: unmet direct dependencies detected for SCHED_THERMAL_PRESSURE
Depends on [n]: SMP [=y] && CPU_FREQ_THERMAL [=n]
Selected by [y]:
- ARM64 [=y]

Revert commit

e17ae7fea871 ("arm, arm64: Select CONFIG_SCHED_THERMAL_PRESSURE")

and re-implement it by making the option default to 'y' for arm64 and arm,
which respects Kconfig dependencies (i.e. will remain 'n' if
CPU_FREQ_THERMAL=n).

Fixes: e17ae7fea871 ("arm, arm64: Select CONFIG_SCHED_THERMAL_PRESSURE")
Reported-by: Qian Cai <cai@lca.pw>
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200729135718.1871-1-valentin.schneider@arm.com

ARM: 8995/1: drop Thumb-2 workaround for ancient binutils

The CONFIG_THUMB2_AVOID_R_ARM_THM_JUMP11 workaround addresses an issue
which was fixed before the oldest supported binutils (2.23 at this time)
were released. So we can remove it now.

Acked-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

ARM: mstar: Add machine for MStar/Sigmastar Armv7 SoCs

Initial support for the MStar/Sigmastar Armv7 based IP camera
and dashcam SoCs.

These chips are interesting in that they contain a Cortex-A7,
peripherals and system memory in a single tiny QFN package that
can be hand soldered allowing almost anyone to embed Linux
in their projects.

Signed-off-by: Daniel Palmer <daniel@0x0f.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

arm, arm64: Select CONFIG_SCHED_THERMAL_PRESSURE

This option now correctly depends on CPU_FREQ_THERMAL, so select it on the
architectures that implement the required functions,
arch_set_thermal_pressure() and arch_get_thermal_pressure().

Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lkml.kernel.org/r/20200712165917.9168-4-valentin.schneider@arm.com

ARM: 8993/1: remove it8152 PCI controller driver

The it8152 PCI host controller was only used by cm-x2xx platforms.
Since these platforms were removed, there is no point to keep it8152
driver.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

ARM: 8991/1: use VFP assembler mnemonics if available

The integrated assembler of Clang 10 and earlier do not allow to access
the VFP registers through the coprocessor load/store instructions:
arch/arm/vfp/vfpmodule.c:342:2: error: invalid operand for instruction
fmxr(FPEXC, fpexc & ~(FPEXC_EX|FPEXC_DEX|FPEXC_FP2V|FPEXC_VV|FPEXC_TRAP_MASK));
^
arch/arm/vfp/vfpinstr.h:79:6: note: expanded from macro 'fmxr'
asm("mcr p10, 7, %0, " vfpreg(_vfp_) ", cr0, 0 @ fmxr " #_vfp_ ", %0"
^
<inline asm>:1:6: note: instantiated into assembly here
mcr p10, 7, r0, cr8, cr0, 0 @ fmxr FPEXC, r0
^

This has been addressed with Clang 11 [0]. However, to support earlier
versions of Clang and for better readability use of VFP assembler
mnemonics still is preferred.

Ideally we would replace this code with the unified assembler language
mnemonics vmrs/vmsr on call sites along with .fpu assembler directives.
The GNU assembler supports the .fpu directive at least since 2.17 (when
documentation has been added). Since Linux requires binutils 2.21 it is
safe to use .fpu directive. However, binutils does not allow to use
FPINST or FPINST2 as an argument to vmrs/vmsr instructions up to
binutils 2.24 (see binutils commit 16d02dc907c5):
arch/arm/vfp/vfphw.S: Assembler messages:
arch/arm/vfp/vfphw.S:162: Error: operand 0 must be FPSID or FPSCR pr FPEXC -- `vmsr FPINST,r6'
arch/arm/vfp/vfphw.S:165: Error: operand 0 must be FPSID or FPSCR pr FPEXC -- `vmsr FPINST2,r8'
arch/arm/vfp/vfphw.S:235: Error: operand 1 must be a VFP extension System Register -- `vmrs r3,FPINST'
arch/arm/vfp/vfphw.S:238: Error: operand 1 must be a VFP extension System Register -- `vmrs r12,FPINST2'

Use as-instr in Kconfig to check if FPINST/FPINST2 can be used. If they
can be used make use of .fpu directives and UAL VFP mnemonics for
register access.

This allows to build vfpmodule.c with Clang and its integrated assembler.

[0] https://reviews.llvm.org/D59733

Link: https://github.com/ClangBuiltLinux/linux/issues/905

Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

dma-mapping: make support for dma ops optional

Avoid the overhead of the dma ops support for tiny builds that only
use the direct mapping.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>

arch: remove HAVE_COPY_THREAD_TLS

All architectures support copy_thread_tls() now, so remove the legacy
copy_thread() function and the HAVE_COPY_THREAD_TLS config option. Everyone
uses the same process creation calling convention based on
copy_thread_tls() and struct kernel_clone_args. This will make it easier to
maintain the core process creation code under kernel/, simplifies the
callpaths and makes the identical for all architectures.

Cc: linux-arch@vger.kernel.org
Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Acked-by: Greentime Hu <green.hu@gmail.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

treewide: replace '---help---' in Kconfig files with 'help'

Since commit 84af7a6194e4 ("checkpatch: kconfig: prefer 'help' over
'---help---'"), the number of '---help---' has been gradually
decreasing, but there are still more than 2400 instances.

This commit finishes the conversion. While I touched the lines,
I also fixed the indentation.

There are a variety of indentation styles found.

a) 4 spaces + '---help---'
b) 7 spaces + '---help---'
c) 8 spaces + '---help---'
d) 1 space + 1 tab + '---help---'
e) 1 tab + '---help---' (correct indentation)
f) 1 tab + 1 space + '---help---'
g) 1 tab + 2 spaces + '---help---'

In order to convert all of them to 1 tab + 'help', I ran the
following commend:

$ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

ARM: 8984/1: Kconfig: set default ZBOOT_ROM_TEXT/BSS value to 0x0

ZBOOT_ROM_TEXT and ZBOOT_ROM_BSS are defined as 'hex' but had a default
of "0". Kconfig will helpfully expand a text entry of 0 to 0x0 but
because this is not the same as the default value it was treated as
being explicitly set when running 'make savedefconfig' so most arm
defconfigs have CONFIG_ZBOOT_ROM_TEXT=0x0 and CONFIG_ZBOOT_ROM_BSS=0x0.

Change the default to 0x0 which will mean next time the defconfigs are
re-generated the spurious config entries will be removed.

Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

ARM: 8980/1: Allow either FLATMEM or SPARSEMEM on the multiplatform build

ARMv7 chips with LPAE can often benefit from SPARSEMEM, as portions of
system memory can be located deep in the 36-bit address space. Allow
FLATMEM or SPARSEMEM to be selectable at compile time; FLATMEM remains
the default.

This is based on Kevin's "[PATCH 3/3] ARM: Allow either FLATMEM or
SPARSEMEM on the multi-v7 build" from [1] and shamelessly rips off his
commit message text above. As Arnd pointed out at [2] there doesn't
seem to be any reason to tie this specifically to ARMv7, so this has
been changed to apply to all multiplatform kernels.

The addition of this option does not change the defaults and a build with
any defconfig will behave the same way as previously.

The only effect this change has is to enable user to change "Memory model"
selection in interactive kernel configuration (menuconfig, xconfig etc).

[1] http://lists.infradead.org/pipermail/linux-arm-kernel/2014-September/286837.html
[2] http://lists.infradead.org/pipermail/linux-arm-kernel/2014-October/298950.html

[ rppt: added ARCH_SELECT_MEMORY_MODEL and updated the changelog ]

Cc: Kevin Cernekee <cernekee@gmail.com>
Tested-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Gregory Fong <gregory.0xf0@gmail.com>
Signed-off-by: Doug Berger <opendmb@gmail.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Mike Rapoport <mike.rapoport@gmail.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

ARM: 8979/1: Remove redundant ARCH_SPARSEMEM_DEFAULT setting

If ARCH_SPARSEMEM_ENABLE=y and ARCH_{FLATMEM,DISCONTIGMEM}_ENABLE=n,
then the logic in mm/Kconfig already makes CONFIG_SPARSEMEM the only
choice. This is true for all of the existing ARM users of
ARCH_SPARSEMEM_ENABLE.

Forcing ARCH_SPARSEMEM_DEFAULT=y if ARCH_SPARSEMEM_ENABLE=y prevents
us from ever defaulting to FLATMEM, so we should remove this setting.

Link: https://lkml.org/lkml/2015/6/4/757

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Tested-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Gregory Fong <gregory.0xf0@gmail.com>
Signed-off-by: Doug Berger <opendmb@gmail.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Mike Rapoport <mike.rapoport@gmail.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

ARM: 8974/1: use SPARSMEM_STATIC when SPARSEMEM is enabled

The commit 3e347261a80b5 ("[PATCH] sparsemem extreme implementation")
made SPARSMEM_EXTREME the default option for configurations that enable
SPARSEMEM.

For ARM systems with handful of memory banks SPARSEMEM_EXTREME is an
overkill.

Ensure that SPARSMEM_STATIC is enabled in the configurations that use
SPARSEMEM.

Fixes: 3e347261a80b5 ("[PATCH] sparsemem extreme implementation")
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

ARM: arch timer: Drop unneeded select GENERIC_CLOCKEVENTS

The ARM Architected timer is available on ARMv7 SoCs only.
As both ARCH_MULTIPLATFORM and ARM_SINGLE_ARMV7M select
GENERIC_CLOCKEVENTS, there is no need for HAVE_ARM_ARCH_TIMER to select
GENERIC_CLOCKEVENTS.

Link: https://lore.kernel.org/r/20200505150722.1575-2-geert+renesas@glider.be
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

bpf: Restrict bpf_probe_read{, str}() only to archs where they work

Given the legacy bpf_probe_read{,str}() BPF helpers are broken on archs
with overlapping address ranges, we should really take the next step to
disable them from BPF use there.

To generally fix the situation, we've recently added new helper variants
bpf_probe_read_{user,kernel}() and bpf_probe_read_{user,kernel}_str().
For details on them, see 6ae08ae3dea2 ("bpf: Add probe_read_{user, kernel}
and probe_read_{user,kernel}_str helpers").

Given bpf_probe_read{,str}() have been around for ~5 years by now, there
are plenty of users at least on x86 still relying on them today, so we
cannot remove them entirely w/o breaking the BPF tracing ecosystem.

However, their use should be restricted to archs with non-overlapping
address ranges where they are working in their current form. Therefore,
move this behind a CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE and
have x86, arm64, arm select it (other archs supporting it can follow-up
on it as well).

For the remaining archs, they can workaround easily by relying on the
feature probe from bpftool which spills out defines that can be used out
of BPF C code to implement the drop-in replacement for old/new kernels
via: bpftool feature probe macro

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/bpf/20200515101118.6508-2-daniel@iogearbox.net

clk: Allow the common clk framework to be selectable

Enable build testing and configuration control of the common clk
framework so that more code coverage and testing can be done on the
common clk framework across various architectures. This also nicely
removes the requirement that architectures must select the framework
when they don't use it in architecture code.

There's one snag with doing this, and that's making sure that randconfig
builds don't select this option when some architecture or platform
implements 'struct clk' outside of the common clk framework. Introduce a
new config option 'HAVE_LEGACY_CLK' to indicate those platforms that
haven't migrated to the common clk framework and therefore shouldn't be
allowed to select this new config option. Also add a note that we hope
one day to remove this config entirely.

Based on a patch by Mark Brown <broonie@kernel.org>.

Cc: Mark Brown <broonie@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Mark Salter <msalter@redhat.com>
Cc: Aurelien Jacquiot <jacquiot.aurelien@gmail.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: <linux-mips@vger.kernel.org>
Cc: <linux-c6x-dev@linux-c6x.org>
Cc: <linux-m68k@lists.linux-m68k.org>
Cc: <linux-arm-kernel@lists.infradead.org>
Cc: <linux-sh@vger.kernel.org>
Link: https://lore.kernel.org/r/1470915049-15249-1-git-send-email-broonie@kernel.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Link: https://lkml.kernel.org/r/20200409064416.83340-8-sboyd@kernel.org
Reviewed-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

ARM: Remove redundant CLKDEV_LOOKUP selects

These platforms select COMMON_CLK indirectly through use of the
ARCH_MULTIPLATFORM config option that they depend on implicitly via some
V7/V6/V5 multi platform config option. The COMMON_CLK config option
already selects CLKDEV_LOOKUP so it's redundant to have this selected
again.

Cc: Tony Prisk <linux@prisktech.co.nz>
Cc: Russell King <linux@armlinux.org.uk>
Cc: <linux-arm-kernel@lists.infradead.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lkml.kernel.org/r/20200409064416.83340-3-sboyd@kernel.org

efi/libstub: Move arm-stub to a common file

Most of the arm-stub code is written in an architecture independent manner.
As a result, RISC-V can reuse most of the arm-stub code.

Rename the arm-stub.c to efi-stub.c so that ARM, ARM64 and RISC-V can use it.
This patch doesn't introduce any functional changes.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Link: https://lore.kernel.org/r/20200415195422.19866-2-atish.patra@wdc.com
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

ARM: versatile: Remove dead sched_clock code

Now that there's a DT based sched_clock driver in
drivers/clocksource/timer-versatile.c and all the Arm reference
platforms are DT only, the non-DT versatile sched_clock code can be
removed.

Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20200409221952.31287-1-robh@kernel.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

ARM: Prepare Realtek RTD1195

Introduce ARCH_REALTEK Kconfig option also for 32-bit Arm.

Override the text offset to cope with boot ROM occupying first 0xa800
bytes and further reservations up to 0xf4000 (compare Device Tree).

Add a custom machine_desc to enforce memory carveout for I/O registers.

Signed-off-by: Andreas Färber <afaerber@suse.de>

arm: Unplug KVM from the build system

As we're about to drop KVM/arm on the floor, carefully unplug
it from the build system.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Olof Johansson <olof@lixom.net>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Vladimir Murzin <vladimir.murzin@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Christoffer Dall <christoffer.dall@arm.com>

ARM/arm64: vdso: Use common vdso clock mode storage

Convert ARM/ARM64 to the generic VDSO clock mode storage. This needs to
happen in one go as they share the clocksource driver.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://lkml.kernel.org/r/20200207124403.363235229@linutronix.de

arm: Remove TIF_NOHZ

Arm entry code calls context tracking from fast path. TIF_NOHZ is unused
and can be safely removed.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King <linux@armlinux.org.uk>

context-tracking: Introduce CONFIG_HAVE_TIF_NOHZ

A few archs (x86, arm, arm64) don't rely anymore on TIF_NOHZ to call
into context tracking on user entry/exit but instead use static keys
(or not) to optimize those calls. Ideally every arch should migrate to
that behaviour in the long run.

Settle a config option to let those archs remove their TIF_NOHZ
definitions.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: David S. Miller <davem@davemloft.net>

asm-generic/tlb: rename HAVE_RCU_TABLE_FREE

Towards a more consistent naming scheme.

[akpm@linux-foundation.org: fix sparc64 Kconfig]
Link: http://lkml.kernel.org/r/20200116064531.483522-7-aneesh.kumar@linux.ibm.com
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ARM: 8952/1: Disable kmemleak on XIP kernels

Kmemleak relies on specific symbols to register the read only data
during init (e.g. __start_ro_after_init).
Trying to build an XIP kernel on arm results in the linking error
reported below because when this option is selected read only data
after init are not allowed since .data is read only (.rodata).

arm-linux-gnueabihf-ld: mm/kmemleak.o: in function `kmemleak_init':
kmemleak.c:(.init.text+0x148): undefined reference to `__end_ro_after_init'
arm-linux-gnueabihf-ld: kmemleak.c:(.init.text+0x14c):
undefined reference to `__end_ro_after_init'
arm-linux-gnueabihf-ld: kmemleak.c:(.init.text+0x150):
undefined reference to `__start_ro_after_init'
arm-linux-gnueabihf-ld: kmemleak.c:(.init.text+0x156):
undefined reference to `__start_ro_after_init'
arm-linux-gnueabihf-ld: kmemleak.c:(.init.text+0x162):
undefined reference to `__start_ro_after_init'
arm-linux-gnueabihf-ld: kmemleak.c:(.init.text+0x16a):
undefined reference to `__start_ro_after_init'
linux/Makefile:1078: recipe for target 'vmlinux' failed

Fix the issue enabling kmemleak only on non XIP kernels.

Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

ARM: 8951/1: Fix Kexec compilation issue.

To perform the reserve_crashkernel() operation kexec uses SECTION_SIZE to
find a memblock in a range.
SECTION_SIZE is not defined for nommu systems. Trying to compile kexec in
these conditions results in a build error:

linux/arch/arm/kernel/setup.c: In function ‘reserve_crashkernel’:
linux/arch/arm/kernel/setup.c:1016:25: error: ‘SECTION_SIZE’ undeclared
(first use in this function); did you mean ‘SECTIONS_WIDTH’?
crash_size, SECTION_SIZE);
^~~~~~~~~~~~
SECTIONS_WIDTH
linux/arch/arm/kernel/setup.c:1016:25: note: each undeclared identifier
is reported only once for each function it appears in
linux/scripts/Makefile.build:265: recipe for target 'arch/arm/kernel/setup.o'
failed

Make KEXEC depend on MMU to fix the compilation issue.

Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

arm: Implement copy_thread_tls

This is required for clone3 which passes the TLS value through a
struct rather than a register.

Signed-off-by: Amanieu d'Antras <amanieu@gmail.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: <stable@vger.kernel.org> # 5.3.x
Link: https://lore.kernel.org/r/20200102172413.654385-4-amanieu@gmail.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

scripts/sorttable: Rename 'sortextable' to 'sorttable'

Use a more generic name for additional table sorting usecases,
such as the upcoming ORC table sorting feature. This tool is
not tied to exception table sorting anymore.

No functional changes intended.

[ mingo: Rewrote the changelog. ]

Signed-off-by: Shile Zhang <shile.zhang@linux.alibaba.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: linux-kbuild@vger.kernel.org
Link: https://lkml.kernel.org/r/20191204004633.88660-6-shile.zhang@linux.alibaba.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

locking/refcount: Consolidate implementations of refcount_t

The generic implementation of refcount_t should be good enough for
everybody, so remove ARCH_HAS_REFCOUNT and REFCOUNT_FULL entirely,
leaving the generic implementation enabled unconditionally.

Signed-off-by: Will Deacon <will@kernel.org>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Kees Cook <keescook@chromium.org>
Tested-by: Hanjun Guo <guohanjun@huawei.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Elena Reshetova <elena.reshetova@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191121115902.2551-9-will@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

dma-direct: provide mmap and get_sgtable method overrides

For dma-direct we know that the DMA address is an encoding of the
physical address that we can trivially decode. Use that fact to
provide implementations that do not need the arch_dma_coherent_to_pfn
architecture hook. Note that we still can only support mmap of
non-coherent memory only if the architecture provides a way to set an
uncached bit in the page tables. This must be true for architectures
that use the generic remap helpers, but other architectures can also
manually select it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Max Filippov <jcmvbkbc@gmail.com>

ARM: ASPEED: update default ARCH_NR_GPIO for ARCH_ASPEED

Increase the max number of GPIOs from default 512 to 1024 for ASPEED
platforms, because Facebook Yamp (AST2500) BMC platform has total 594
GPIO pins (232 provided by ASPEED SoC, and 362 by I/O Expanders).

Link: https://lore.kernel.org/r/20191031014040.12898-1-rentao.bupt@gmail.com
Signed-off-by: Tao Ren <rentao.bupt@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Olof Johansson <olof@lixom.net>

ARM: 8928/1: ARM_ERRATA_775420: Spelling s/date/data/

Caching dates is never a good idea ;-)

Fixes: 7253b85cc62d6ff8 ("ARM: 7541/1: Add ARM ERRATA 775420 workaround")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

arm: use generic mmap top-down layout and brk randomization

arm uses a top-down mmap layout by default that exactly fits the generic
functions, so get rid of arch specific code and use the generic version by
selecting ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT.

As ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT selects ARCH_HAS_ELF_RANDOMIZE,
use the generic version of arch_randomize_brk since it also fits. Note
that this commit also removes the possibility for arm to have elf
randomization and no MMU: without MMU, the security added by randomization
is worth nothing.

Note that it is safe to remove STACK_RND_MASK since it matches the default
value.

Link: http://lkml.kernel.org/r/20190730055113.23635-9-alex@ghiti.fr
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Acked-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: James Hogan <jhogan@kernel.org>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ARM: 8905/1: Emit __gnu_mcount_nc when using Clang 10.0.0 or newer

Currently, multi_v7_defconfig + CONFIG_FUNCTION_TRACER fails to build
with clang:

arm-linux-gnueabi-ld: kernel/softirq.o: in function `_local_bh_enable':
softirq.c:(.text+0x504): undefined reference to `mcount'
arm-linux-gnueabi-ld: kernel/softirq.o: in function `__local_bh_enable_ip':
softirq.c:(.text+0x58c): undefined reference to `mcount'
arm-linux-gnueabi-ld: kernel/softirq.o: in function `do_softirq':
softirq.c:(.text+0x6c8): undefined reference to `mcount'
arm-linux-gnueabi-ld: kernel/softirq.o: in function `irq_enter':
softirq.c:(.text+0x75c): undefined reference to `mcount'
arm-linux-gnueabi-ld: kernel/softirq.o: in function `irq_exit':
softirq.c:(.text+0x840): undefined reference to `mcount'
arm-linux-gnueabi-ld: kernel/softirq.o:softirq.c:(.text+0xa50): more undefined references to `mcount' follow

clang can emit a working mcount symbol, __gnu_mcount_nc, when
'-meabi gnu' is passed to it. Until r369147 in LLVM, this was
broken and caused the kernel not to boot with '-pg' because the
calling convention was not correct. Always build with '-meabi gnu'
when using clang but ensure that '-pg' (which is added with
CONFIG_FUNCTION_TRACER and its prereq CONFIG_HAVE_FUNCTION_TRACER)
cannot be added with it unless this is fixed (which means using
clang 10.0.0 and newer).

Link: https://github.com/ClangBuiltLinux/linux/issues/35
Link: https://bugs.llvm.org/show_bug.cgi?id=33845
Link: https://github.com/llvm/llvm-project/commit/16fa8b09702378bacfa3d07081afe6b353b99e60

Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

ARM: davinci: support multiplatform build for ARM v5

Add modifications necessary to make davinci part of the ARM v5
multiplatform build.

Move the arch-specific configuration out of arch/arm/Kconfig and
into mach-davinci/Kconfig. Remove the sub-menu for DaVinci
implementations (they'll be visible directly under the system type.
Select all necessary options not already selected by ARCH_MULTI_V5.
Update davinci_all_defconfig. Explicitly include the mach-specific
headers in mach-davinci/Makefile.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Acked-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

dma-mapping: remove arch_dma_mmap_pgprot

arch_dma_mmap_pgprot is used for two things:

1) to override the "normal" uncached page attributes for mapping
memory coherent to devices that can't snoop the CPU caches
2) to provide the special DMA_ATTR_WRITE_COMBINE semantics on older
arm systems and some mips platforms

Replace one with the pgprot_dmacoherent macro that is already provided
by arm and much simpler to use, and lift the DMA_ATTR_WRITE_COMBINE
handling to common code with an explicit arch opt-in.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> # m68k
Acked-by: Paul Burton <paul.burton@mips.com> # mips

ARM: 8875/1: Kconfig: default to AEABI w/ Clang

Clang produces references to __aeabi_uidivmod and __aeabi_idivmod for
arm-linux-gnueabi and arm-linux-gnueabihf targets incorrectly when AEABI
is not selected (such as when OABI_COMPAT is selected).

While this means that OABI userspaces wont be able to upgraded to
kernels built with Clang, it means that boards that don't enable AEABI
like s3c2410_defconfig will stop failing to link in KernelCI when built
with Clang.

Link: https://github.com/ClangBuiltLinux/linux/issues/482
Link: https://groups.google.com/forum/#!msg/clang-built-linux/yydsAAux5hk/GxjqJSW-AQAJ

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

arm: select the dma-noncoherent symbols for all swiotlb builds

We need to provide the arch hooks for non-coherent dma-direct
and swiotlb for all swiotlb builds, not just when LPAS is enabled.
Without that the Xen build that selects SWIOTLB indirectly through
SWIOTLB_XEN fails to build.

Fixes: ad3c7b18c5b3 ("arm: use swiotlb for bounce buffering on LPAE configs")
Reported-by: Stefan Wahren <wahrenst@gmx.net>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Stefan Wahren <wahrenst@gmx.net>

ARM: lpc32xx: allow multiplatform build

All preparation work is done, so the platform can finally
be moved into ARCH_MULTIPLATFORM. This requires a small
change to the defconfig file to enable the platform.

Link: https://lore.kernel.org/r/20190809144043.476786-14-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: remove Intel iop33x and iop13xx support

There are three families of IOP machines we support in Linux: iop32x
(which includes EP80219), iop33x and iop13xx (aka IOP34x aka WP8134x).

All products we support in the kernel are based on the first of these,
iop32x, the other families only ever supported the Intel reference
boards but no actual machine anyone could ever buy.

While one could clearly make them all three work in a single kernel
with some work, this takes the easy way out, removing the later two
platforms entirely, under the assumption that there are no remaining
users.

Earlier versions of OpenWRT and Debian both had support for iop32x
but not the others, and they both dropped iop32x as well in their 2015
releases.

Link: https://lore.kernel.org/r/20190809163334.489360-1-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Wolfram Sang <wsa@the-dreams.de> # for I2C parts
Acked-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Martin Michlmayr <tbm@cyrius.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: remove w90x900 platform

This removes the old Winbond w90x900 platform, also known
as Nuvoton NUC900. Wan Zongshun originally contributed
the port and maintained it since then.

From all I can tell, this platform is no longer being used
with modern kernels, based on various indications:

- The supported chips (nuc910/950/960) are no longer marketed
by the manufacturer

- Newer chips from the same family (nuc97x, nuc980, n329x)
that are still marketed have Linux BSPs but those were never
submitted for upstream inclusion.

- The last patch from the platform maintainer was in 2011.

- All patches to w90x900 platform specific files afterwards
are cleanups that were apparently done without access to
test hardware.

- Both the website and the email address listed in the
MAINTAINERS have become unreachable.

Link: https://lore.kernel.org/r/20190809202749.742267-17-arnd@arndb.de
Cc: "Wanzongshun (Vincent)" <wanzongshun@huawei.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: remove ks8695 platform

ks8695 is an older SoC originally made by Kendin, which was later acquired
by Micrel, and subsequently by Microchip.

The platform port was originally contributed by Andrew Victor and Ben
Dooks, and later maintained by Greg Ungerer.

When I recently submitted cleanups, but Greg noted that the platform no
longer boots and nobody is using it any more, we decided to remove it.

Link: https://lore.kernel.org/r/20190809202749.742267-2-arnd@arndb.de
Cc: Andrew Victor <linux@maxim.org.za>
Acked-by: Ben Dooks <ben-linux@fluff.org>
Link: https://wikidevi.com/wiki/Micrel
Link: https://lore.kernel.org/linux-arm-kernel/2bc41895-d4f9-896c-0726-0b2862fcbf25@kernel.org/
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Greg Ungerer <gerg@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

ARM: davinci: enable the clocksource driver for DT mode

Switch all davinci boards supporting device tree to using the new
clocksource driver: remove the previous OF_TIMER_DECLARE() from
mach-davinci and select davinci-timer for ARCH_DAVINCI.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: David Lechner <david@lechnology.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>

docs: admin-guide: add a series of orphaned documents

There are lots of documents that belong to the admin-guide but
are on random places (most under Documentation root dir).

Move them to the admin guide.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

docs: admin-guide: add kdump documentation into it

The Kdump documentation describes procedures with admins use
in order to solve issues on their systems.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

docs: arm: convert docs to ReST and rename to *.rst

Converts ARM the text files to ReST, preparing them to be an
architecture book.

The conversion is actually:
- add blank lines and identation in order to identify paragraphs;
- fix tables markups;
- add some lists markups;
- mark literal blocks;
- adjust title markups.

At its new index.rst, let's add a :orphan: while this is not linked to
the main index.rst file, in order to avoid build warnings.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Reviewed-by Corentin Labbe <clabbe.montjoie@gmail.com> # For sun4i-ss

mm: rename CONFIG_HAVE_GENERIC_GUP to CONFIG_HAVE_FAST_GUP

We only support the generic GUP now, so rename the config option to
be more clear, and always use the mm/Kconfig definition of the
symbol and select it from the arch Kconfigs.

Link: http://lkml.kernel.org/r/20190625143715.1689-11-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Khalid Aziz <khalid.aziz@oracle.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Miller <davem@davemloft.net>
Cc: James Hogan <jhogan@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arm: remove ARCH_SELECT_MEMORY_MODEL

Patch series "remove ARCH_SELECT_MEMORY_MODEL where it has no effect".

For several architectures the ARCH_SELECT_MEMORY_MODEL has no real effect
because the dependencies for the memory model are always evaluated to a
single value.

Remove the ARCH_SELECT_MEMORY_MODEL from the Kconfigs for these
architectures.

This patch (of 3):

The ARCH_SELECT_MEMORY_MODEL in arch/arm/Kconfig is enabled only when
ARCH_SPARSEMEM_ENABLE=y. But in this case, ARCH_SPARSEMEM_DEFAULT is also
enabled and this in turn enables SPARSEMEM_MANUAL.

Since there is no definition of ARCH_FLATMEM_ENABLE in arch/arm/Kconfig,
SPARSEMEM_MANUAL is the only enabled memory model, hence the final
selection will evaluate to SPARSEMEM=y.

Since ARCH_SPARSEMEM_ENABLE is set to 'y' only by several sub-arch
configurations, the default for must sub-arches would be the falback to
FLATMEM regardless of ARCH_SELECT_MEMORY_MODEL.

Link: http://lkml.kernel.org/r/1556740577-4140-2-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Russell King <linux@armlinux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ARM: sa1100: convert to common clock framework

Convert sa1100 to use the common clock framework.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

binfmt_flat: add a ARCH_HAS_BINFMT_FLAT option

Allow architectures to opt into ARCH_HAS_BINFMT_FLAT support instead of
assuming that all nommu ports support the format.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>

binfmt_flat: replace flat_argvp_envp_on_stack with a Kconfig variable

This will eventually allow us to kill the need for an <asm/flat.h> for
many cases.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com>
Reviewed-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>

ARM: 8862/1: errata: 814220-B-Cache maintenance by set/way operations can execute out of order

The v7 ARM states that all cache and branch predictor maintenance operations
that do not specify an address execute, relative to each other, in program
order. However, because of this erratum, an L2 set/way cache maintenance
operation can overtake an L1 set/way cache maintenance operation, this would
cause the data corruption.

This ERRATA affected the Cortex-A7 and present in r0p2, r0p3, r0p4, r0p5.

This patch is the SW workaround by adding a DSB before changing cache levels as
the ARM ERRATA: ARM/MP: 814220 told in the ARM ERRATA documentation.

Signed-off-by: Jason Liu <r64343@freescale.com>
Signed-off-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

ARM: 8861/1: errata: Workaround errata A12 857271 / A17 857272

This adds support for working around errata A12 857271 / A17 857272.
These errata were causing hangs on rk3288-based Chromebooks and it was
confirmed that this workaround fixed the problems. In the Chrome OS
3.14 kernel this was treated as two errata: ERRATA_FOOBAR [1] and
ERRATA_CR711784 [2]. Apparently the two errata got lumped together at
some point in time.

Let's actually get the workaround landed.

[1] https://crrev.com/c/342753
[2] https://crbug.com/711784

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Sonny Rao <sonnyrao@chromium.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

docs: kdump: convert docs to ReST and rename to *.rst

Convert kdump documentation to ReST and add it to the
user faced manual, as the documents are mainly focused on
sysadmins that would be enabling kdump.

Note: the vmcoreinfo.rst has one very long title on one of its
sub-sections:

PG_lru|PG_private|PG_swapcache|PG_swapbacked|PG_slab|PG_hwpoision|PG_head_mask|PAGE_BUDDY_MAPCOUNT_VALUE(~PG_buddy)|PAGE_OFFLINE_MAPCOUNT_VALUE(~PG_offline)

I opted to break this one, into two entries with the same content,
in order to make it easier to display after being parsed in html and PDF.

The conversion is actually:
- add blank lines and identation in order to identify paragraphs;
- fix tables markups;
- add some lists markups;
- mark literal blocks;
- adjust title markups.

At its new index.rst, let's add a :orphan: while this is not linked to
the main index.rst file, in order to avoid build warnings.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

ARM: riscpc: enable chained scatterlist support

There's no reason why we can't enable chained scatterlist for RiscPC,
we already support chained scatterlists in the IOMD DMA support code.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

docs: fix broken documentation links

Mostly due to x86 and acpi conversion, several documentation
links are still pointing to the old file. Fix them.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Reviewed-by: Wolfram Sang <wsa@the-dreams.de>
Reviewed-by: Sven Van Asbroeck <TheSven73@gmail.com>
Reviewed-by: Bhupesh Sharma <bhsharma@redhat.com>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

ARM: delete netx machine

After discussing with the subarch maintainers and Hilscher,
we concluded that the netx subarchitecture (Netx 100/500)
is no longer maintained or tested, and noone will miss it
if we delete it. So delete it.

There is a newer Netx 4000 architecture which we may see
included at some point, but this will be supported using
the standard multiplatform and devicetree mechanisms and is
easier to develop from scratch.

Cc: Michael Trensch <MTrensch@hilscher.com>
Acked-By: Robert Schwebel <r.schwebel@pengutronix.de>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

mm: memblock: make keeping memblock memory opt-in rather than opt-out

Most architectures do not need the memblock memory after the page
allocator is initialized, but only few enable ARCH_DISCARD_MEMBLOCK in the
arch Kconfig.

Replacing ARCH_DISCARD_MEMBLOCK with ARCH_KEEP_MEMBLOCK and inverting the
logic makes it clear which architectures actually use memblock after
system initialization and skips the necessity to add ARCH_DISCARD_MEMBLOCK
to the architectures that are still missing that option.

Link: http://lkml.kernel.org/r/1556102150-32517-1-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

initramfs: move the legacy keepinitrd parameter to core code

No need to handle the freeing disable in arch code when we already have a
core hook (and a different name for the option) for it.

Link: http://lkml.kernel.org/r/20190213174621.29297-7-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Catalin Marinas <catalin.marinas@arm.com> [arm64]
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org> [m68k]
Cc: Steven Price <steven.price@arm.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ARM: riscpc: replace gettimeoffset() with clocksource

Replace the old gettimeoffset() interface (which became buggy in
several ways) with a clocksource that atomically reads the count
and status from the timer, and corrects the count as appropriate
ensuring proper resolution of time without time warping backwards.

We keep the original periodic timer non-clock event implementation
to provide the kernel with a regular source of interrupts, which
are required to keep the clocksource properly updated.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

ARM: fix function graph tracer and unwinder dependencies

Naresh Kamboju recently reported that the function-graph tracer crashes
on ARM. The function-graph tracer assumes that the kernel is built with
frame pointers.

We explicitly disabled the function-graph tracer when building Thumb2,
since the Thumb2 ABI doesn't have frame pointers.

We recently changed the way the unwinder method was selected, which
seems to have made it more likely that we can end up with the function-
graph tracer enabled but without the kernel built with frame pointers.

Fix up the function graph tracer dependencies so the option is not
available when we have no possibility of having frame pointers, and
adjust the dependencies on the unwinder option to hide the non-frame
pointer unwinder options if the function-graph tracer is enabled.

Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

ARM: ixp4xx: Switch to use new timer driver

This augments the IXP4xx to select and use the new
timer driver in drivers/clocksource and removes the old
code in the machine.

Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>