#
5a00bfd6 |
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15-Feb-2024 |
Ryan Roberts <ryan.roberts@arm.com> |
arm64/mm: new ptep layer to manage contig bit Create a new layer for the in-table PTE manipulation APIs. For now, The existing API is prefixed with double underscore to become the arch-private API and the public API is just a simple wrapper that calls the private API. The public API implementation will subsequently be used to transparently manipulate the contiguous bit where appropriate. But since there are already some contig-aware users (e.g. hugetlb, kernel mapper), we must first ensure those users use the private API directly so that the future contig-bit manipulations in the public API do not interfere with those existing uses. The following APIs are treated this way: - ptep_get - set_pte - set_ptes - pte_clear - ptep_get_and_clear - ptep_test_and_clear_young - ptep_clear_flush_young - ptep_set_wrprotect - ptep_set_access_flags Link: https://lkml.kernel.org/r/20240215103205.2607016-11-ryan.roberts@arm.com Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> Tested-by: John Hubbard <jhubbard@nvidia.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Barry Song <21cnbao@gmail.com> Cc: Borislav Petkov (AMD) <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Morse <james.morse@arm.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Cc: Yang Shi <shy828301@gmail.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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#
53273655 |
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15-Feb-2024 |
Ryan Roberts <ryan.roberts@arm.com> |
arm64/mm: convert READ_ONCE(*ptep) to ptep_get(ptep) There are a number of places in the arch code that read a pte by using the READ_ONCE() macro. Refactor these call sites to instead use the ptep_get() helper, which itself is a READ_ONCE(). Generated code should be the same. This will benefit us when we shortly introduce the transparent contpte support. In this case, ptep_get() will become more complex so we now have all the code abstracted through it. Link: https://lkml.kernel.org/r/20240215103205.2607016-8-ryan.roberts@arm.com Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> Tested-by: John Hubbard <jhubbard@nvidia.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Barry Song <21cnbao@gmail.com> Cc: Borislav Petkov (AMD) <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Morse <james.morse@arm.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Cc: Yang Shi <shy828301@gmail.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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#
b8466fe8 |
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17-Oct-2023 |
Arnd Bergmann <arnd@arndb.de> |
efi: move screen_info into efi init code After the vga console no longer relies on global screen_info, there are only two remaining use cases: - on the x86 architecture, it is used for multiple boot methods (bzImage, EFI, Xen, kexec) to commucate the initial VGA or framebuffer settings to a number of device drivers. - on other architectures, it is only used as part of the EFI stub, and only for the three sysfb framebuffers (simpledrm, simplefb, efifb). Remove the duplicate data structure definitions by moving it into the efi-init.c file that sets it up initially for the EFI case, leaving x86 as an exception that retains its own definition for non-EFI boots. The added #ifdefs here are optional, I added them to further limit the reach of screen_info to configurations that have at least one of the users enabled. Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Javier Martinez Canillas <javierm@redhat.com> Acked-by: Helge Deller <deller@gmx.de> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/20231017093947.3627976-1-arnd@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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#
bbbb6577 |
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16-Oct-2023 |
Mark Rutland <mark.rutland@arm.com> |
arm64: Avoid cpus_have_const_cap() for ARM64_HAS_BTI In system_supports_bti() we use cpus_have_const_cap() to check for ARM64_HAS_BTI, but this is not necessary and alternative_has_cap_*() or cpus_have_final_*cap() would be preferable. For historical reasons, cpus_have_const_cap() is more complicated than it needs to be. Before cpucaps are finalized, it will perform a bitmap test of the system_cpucaps bitmap, and once cpucaps are finalized it will use an alternative branch. This used to be necessary to handle some race conditions in the window between cpucap detection and the subsequent patching of alternatives and static branches, where different branches could be out-of-sync with one another (or w.r.t. alternative sequences). Now that we use alternative branches instead of static branches, these are all patched atomically w.r.t. one another, and there are only a handful of cases that need special care in the window between cpucap detection and alternative patching. Due to the above, it would be nice to remove cpus_have_const_cap(), and migrate callers over to alternative_has_cap_*(), cpus_have_final_cap(), or cpus_have_cap() depending on when their requirements. This will remove redundant instructions and improve code generation, and will make it easier to determine how each callsite will behave before, during, and after alternative patching. When CONFIG_ARM64_BTI_KERNEL=y, the ARM64_HAS_BTI cpucap is a strict boot cpu feature which is detected and patched early on the boot cpu. All uses guarded by CONFIG_ARM64_BTI_KERNEL happen after the boot CPU has detected ARM64_HAS_BTI and patched boot alternatives, and hence can safely use alternative_has_cap_*() or cpus_have_final_boot_cap(). Regardless of CONFIG_ARM64_BTI_KERNEL, all other uses of ARM64_HAS_BTI happen after system capabilities have been finalized and alternatives have been patched. Hence these can safely use alternative_has_cap_*) or cpus_have_final_cap(). This patch splits system_supports_bti() into system_supports_bti() and system_supports_bti_kernel(), with the former handling where the cpucap affects userspace functionality, and ther latter handling where the cpucap affects kernel functionality. The use of cpus_have_const_cap() is replaced by cpus_have_final_cap() in cpus_have_const_cap, and cpus_have_final_boot_cap() in system_supports_bti_kernel(). This will avoid generating code to test the system_cpucaps bitmap and should be better for all subsequent calls at runtime. The use of cpus_have_final_cap() and cpus_have_final_boot_cap() will make it easier to spot if code is chaanged such that these run before the ARM64_HAS_BTI cpucap is guaranteed to have been finalized. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Mark Brown <broonie@kernel.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Suzuki K Poulose <suzuki.poulose@arm.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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#
8b0d1354 |
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05-Jul-2023 |
Thomas Zimmermann <tzimmermann@suse.de> |
efi: Do not include <linux/screen_info.h> from EFI header The header file <linux/efi.h> does not need anything from <linux/screen_info.h>. Declare struct screen_info and remove the include statements. Update a number of source files that require struct screen_info's definition. v2: * update loongarch (Jingfeng) Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Javier Martinez Canillas <javierm@redhat.com> Reviewed-by: Sui Jingfeng <suijingfeng@loongson.cn> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Link: https://patchwork.freedesktop.org/patch/msgid/20230706104852.27451-2-tzimmermann@suse.de
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#
c37ce235 |
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08-Aug-2023 |
Ard Biesheuvel <ardb@kernel.org> |
efi/arm64: Move EFI runtime call setup/teardown helpers out of line Only the arch_efi_call_virt() macro that some architectures override needs to be a macro, given that it is variadic and encapsulates calls via function pointers that have different prototypes. The associated setup and teardown code are not special in this regard, and don't need to be instantiated at each call site. So turn them into ordinary C functions and move them out of line. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
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#
0e68b551 |
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15-Feb-2023 |
Pierre Gondois <pierre.gondois@arm.com> |
arm64: efi: Make efi_rt_lock a raw_spinlock Running a rt-kernel base on 6.2.0-rc3-rt1 on an Ampere Altra outputs the following: BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:46 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 9, name: kworker/u320:0 preempt_count: 2, expected: 0 RCU nest depth: 0, expected: 0 3 locks held by kworker/u320:0/9: #0: ffff3fff8c27d128 ((wq_completion)efi_rts_wq){+.+.}-{0:0}, at: process_one_work (./include/linux/atomic/atomic-long.h:41) #1: ffff80000861bdd0 ((work_completion)(&efi_rts_work.work)){+.+.}-{0:0}, at: process_one_work (./include/linux/atomic/atomic-long.h:41) #2: ffffdf7e1ed3e460 (efi_rt_lock){+.+.}-{3:3}, at: efi_call_rts (drivers/firmware/efi/runtime-wrappers.c:101) Preemption disabled at: efi_virtmap_load (./arch/arm64/include/asm/mmu_context.h:248) CPU: 0 PID: 9 Comm: kworker/u320:0 Tainted: G W 6.2.0-rc3-rt1 Hardware name: WIWYNN Mt.Jade Server System B81.03001.0005/Mt.Jade Motherboard, BIOS 1.08.20220218 (SCP: 1.08.20220218) 2022/02/18 Workqueue: efi_rts_wq efi_call_rts Call trace: dump_backtrace (arch/arm64/kernel/stacktrace.c:158) show_stack (arch/arm64/kernel/stacktrace.c:165) dump_stack_lvl (lib/dump_stack.c:107 (discriminator 4)) dump_stack (lib/dump_stack.c:114) __might_resched (kernel/sched/core.c:10134) rt_spin_lock (kernel/locking/rtmutex.c:1769 (discriminator 4)) efi_call_rts (drivers/firmware/efi/runtime-wrappers.c:101) [...] This seems to come from commit ff7a167961d1 ("arm64: efi: Execute runtime services from a dedicated stack") which adds a spinlock. This spinlock is taken through: efi_call_rts() \-efi_call_virt() \-efi_call_virt_pointer() \-arch_efi_call_virt_setup() Make 'efi_rt_lock' a raw_spinlock to avoid being preempted. [ardb: The EFI runtime services are called with a different set of translation tables, and are permitted to use the SIMD registers. The context switch code preserves/restores neither, and so EFI calls must be made with preemption disabled, rather than only disabling migration.] Fixes: ff7a167961d1 ("arm64: efi: Execute runtime services from a dedicated stack") Signed-off-by: Pierre Gondois <pierre.gondois@arm.com> Cc: <stable@vger.kernel.org> # v6.1+ Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
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#
1d959312 |
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01-Feb-2023 |
Ard Biesheuvel <ardb@kernel.org> |
efi: arm64: Wire up BTI annotation in memory attributes table UEFI v2.10 extends the EFI memory attributes table with a flag that indicates whether or not all RuntimeServicesCode regions were constructed with BTI landing pads, permitting the OS to map these regions with BTI restrictions enabled. So let's take this into account on arm64. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Will Deacon <will@kernel.org>
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#
cf1d2ffc |
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01-Feb-2023 |
Ard Biesheuvel <ardb@kernel.org> |
efi: Discover BTI support in runtime services regions Add the generic plumbing to detect whether or not the runtime code regions were constructed with BTI/IBT landing pads by the firmware, permitting the OS to enable enforcement when mapping these regions into the OS's address space. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org>
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#
8a9a1a18 |
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28-Oct-2022 |
Ard Biesheuvel <ardb@kernel.org> |
arm64: efi: Avoid workqueue to check whether EFI runtime is live Comparing current_work() against efi_rts_work.work is sufficient to decide whether current is currently running EFI runtime services code at any level in its call stack. However, there are other potential users of the EFI runtime stack, such as the ACPI subsystem, which may invoke efi_call_virt_pointer() directly, and so any sync exceptions occurring in firmware during those calls are currently misidentified. So instead, let's check whether the stashed value of the thread stack pointer points into current's thread stack. This can only be the case if current was interrupted while running EFI runtime code. Note that this implies that we should clear the stashed value after switching back, to avoid false positives. Reviewed-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
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#
e8dfdf31 |
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28-Oct-2022 |
Ard Biesheuvel <ardb@kernel.org> |
arm64: efi: Recover from synchronous exceptions occurring in firmware Unlike x86, which has machinery to deal with page faults that occur during the execution of EFI runtime services, arm64 has nothing like that, and a synchronous exception raised by firmware code brings down the whole system. With more EFI based systems appearing that were not built to run Linux (such as the Windows-on-ARM laptops based on Qualcomm SOCs), as well as the introduction of PRM (platform specific firmware routines that are callable just like EFI runtime services), we are more likely to run into issues of this sort, and it is much more likely that we can identify and work around such issues if they don't bring down the system entirely. Since we already use a EFI runtime services call wrapper in assembler, we can quite easily add some code that captures the execution state at the point where the call is made, allowing us to revert to this state and proceed execution if the call triggered a synchronous exception. Given that the kernel and the firmware don't share any data structures that could end up in an indeterminate state, we can happily continue running, as long as we mark the EFI runtime services as unavailable from that point on. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com>
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#
ff7a1679 |
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05-Dec-2022 |
Ard Biesheuvel <ardb@kernel.org> |
arm64: efi: Execute runtime services from a dedicated stack With the introduction of PRMT in the ACPI subsystem, the EFI rts workqueue is no longer the only caller of efi_call_virt_pointer() in the kernel. This means the EFI runtime services lock is no longer sufficient to manage concurrent calls into firmware, but also that firmware calls may occur that are not marshalled via the workqueue mechanism, but originate directly from the caller context. For added robustness, and to ensure that the runtime services have 8 KiB of stack space available as per the EFI spec, introduce a spinlock protected EFI runtime stack of 8 KiB, where the spinlock also ensures serialization between the EFI rts workqueue (which itself serializes EFI runtime calls) and other callers of efi_call_virt_pointer(). While at it, use the stack pivot to avoid reloading the shadow call stack pointer from the ordinary stack, as doing so could produce a gadget to defeat it. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
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7572ac3c |
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30-Nov-2022 |
Ard Biesheuvel <ardb@kernel.org> |
arm64: efi: Revert "Recover from synchronous exceptions ..." This reverts commit 23715a26c8d81291, which introduced some code in assembler that manipulates both the ordinary and the shadow call stack pointer in a way that could potentially be taken advantage of. So let's revert it, and do a better job the next time around. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
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#
9b9eaee9 |
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06-Nov-2022 |
Ard Biesheuvel <ardb@kernel.org> |
arm64: efi: Fix handling of misaligned runtime regions and drop warning Currently, when mapping the EFI runtime regions in the EFI page tables, we complain about misaligned regions in a rather noisy way, using WARN(). Not only does this produce a lot of irrelevant clutter in the log, it is factually incorrect, as misaligned runtime regions are actually allowed by the EFI spec as long as they don't require conflicting memory types within the same 64k page. So let's drop the warning, and tweak the code so that we - take both the start and end of the region into account when checking for misalignment - only revert to RWX mappings for non-code regions if misaligned code regions are also known to exist. Cc: <stable@vger.kernel.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
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#
23715a26 |
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28-Oct-2022 |
Ard Biesheuvel <ardb@kernel.org> |
arm64: efi: Recover from synchronous exceptions occurring in firmware Unlike x86, which has machinery to deal with page faults that occur during the execution of EFI runtime services, arm64 has nothing like that, and a synchronous exception raised by firmware code brings down the whole system. With more EFI based systems appearing that were not built to run Linux (such as the Windows-on-ARM laptops based on Qualcomm SOCs), as well as the introduction of PRM (platform specific firmware routines that are callable just like EFI runtime services), we are more likely to run into issues of this sort, and it is much more likely that we can identify and work around such issues if they don't bring down the system entirely. Since we already use a EFI runtime services call wrapper in assembler, we can quite easily add some code that captures the execution state at the point where the call is made, allowing us to revert to this state and proceed execution if the call triggered a synchronous exception. Given that the kernel and the firmware don't share any data structures that could end up in an indeterminate state, we can happily continue running, as long as we mark the EFI runtime services as unavailable from that point on. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com>
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#
9b16c213 |
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04-Aug-2021 |
Michael Kelley <mikelley@microsoft.com> |
arm64: efi: Export screen_info The Hyper-V frame buffer driver may be built as a module, and it needs access to screen_info. So export screen_info. Signed-off-by: Michael Kelley <mikelley@microsoft.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Marc Zyngier <maz@kernel.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/1628092359-61351-5-git-send-email-mikelley@microsoft.com Signed-off-by: Wei Liu <wei.liu@kernel.org>
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33def849 |
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21-Oct-2020 |
Joe Perches <joe@perches.com> |
treewide: Convert macro and uses of __section(foo) to __section("foo") Use a more generic form for __section that requires quotes to avoid complications with clang and gcc differences. Remove the quote operator # from compiler_attributes.h __section macro. Convert all unquoted __section(foo) uses to quoted __section("foo"). Also convert __attribute__((section("foo"))) uses to __section("foo") even if the __attribute__ has multiple list entry forms. Conversion done using the script at: https://lore.kernel.org/lkml/75393e5ddc272dc7403de74d645e6c6e0f4e70eb.camel@perches.com/2-convert_section.pl Signed-off-by: Joe Perches <joe@perches.com> Reviewed-by: Nick Desaulniers <ndesaulniers@gooogle.com> Reviewed-by: Miguel Ojeda <ojeda@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
8b1e0f81 |
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11-Jul-2019 |
Anshuman Khandual <anshuman.khandual@arm.com> |
mm/pgtable: drop pgtable_t variable from pte_fn_t functions Drop the pgtable_t variable from all implementation for pte_fn_t as none of them use it. apply_to_pte_range() should stop computing it as well. Should help us save some cycles. Link: http://lkml.kernel.org/r/1556803126-26596-1-git-send-email-anshuman.khandual@arm.com Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Acked-by: Matthew Wilcox <willy@infradead.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Logan Gunthorpe <logang@deltatee.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: <jglisse@redhat.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
d2912cb1 |
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04-Jun-2019 |
Thomas Gleixner <tglx@linutronix.de> |
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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#
7e611e7d |
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08-Mar-2018 |
Ard Biesheuvel <ardb@kernel.org> |
efi/arm64: Check whether x18 is preserved by runtime services calls Whether or not we will ever decide to start using x18 as a platform register in Linux is uncertain, but by that time, we will need to ensure that UEFI runtime services calls don't corrupt it. So let's start issuing warnings now for this, and increase the likelihood that these firmware images have all been replaced by that time. This has been fixed on the EDK2 side in commit: 6d73863b5464 ("BaseTools/tools_def AARCH64: mark register x18 as reserved") dated July 13, 2017. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Will Deacon <will.deacon@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20180308080020.22828-6-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
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#
20a004e7 |
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15-Feb-2018 |
Will Deacon <will@kernel.org> |
arm64: mm: Use READ_ONCE/WRITE_ONCE when accessing page tables In many cases, page tables can be accessed concurrently by either another CPU (due to things like fast gup) or by the hardware page table walker itself, which may set access/dirty bits. In such cases, it is important to use READ_ONCE/WRITE_ONCE when accessing page table entries so that entries cannot be torn, merged or subject to apparent loss of coherence due to compiler transformations. Whilst there are some scenarios where this cannot happen (e.g. pinned kernel mappings for the linear region), the overhead of using READ_ONCE /WRITE_ONCE everywhere is minimal and makes the code an awful lot easier to reason about. This patch consistently uses these macros in the arch code, as well as explicitly namespacing pointers to page table entries from the entries themselves by using adopting a 'p' suffix for the former (as is sometimes used elsewhere in the kernel source). Tested-by: Yury Norov <ynorov@caviumnetworks.com> Tested-by: Richard Ruigrok <rruigrok@codeaurora.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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#
1e9de1d2 |
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02-Jan-2018 |
Ard Biesheuvel <ardb@kernel.org> |
arm64/efi: Ignore EFI_MEMORY_XP attribute if RP and/or WP are set The UEFI memory map is a bit vague about how to interpret the EFI_MEMORY_XP attribute when it is combined with EFI_MEMORY_RP and/or EFI_MEMORY_WP, which have retroactively been redefined as cacheability attributes rather than permission attributes. So let's ignore EFI_MEMORY_XP if _RP and/or _WP are also set. In this case, it is likely that they are being used to describe the capability of the region (i.e., whether it has the controls to reconfigure it as non-executable) rather than the nature of the contents of the region (i.e., whether it contains data that we will never attempt to execute) Reported-by: Stephen Boyd <sboyd@codeaurora.org> Tested-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Arvind Yadav <arvind.yadav.cs@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tyler Baicar <tbaicar@codeaurora.org> Cc: Vasyl Gomonovych <gomonovych@gmail.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20180102181042.19074-3-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
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#
bb817bef |
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02-Jun-2017 |
Ard Biesheuvel <ardb@kernel.org> |
efi/arm: Enable DMI/SMBIOS Wire up the existing arm64 support for SMBIOS tables (aka DMI) for ARM as well, by moving the arm64 init code to drivers/firmware/efi/arm-runtime.c (which is shared between ARM and arm64), and adding a asm/dmi.h header to ARM that defines the mapping routines for the firmware tables. This allows userspace to access these tables to discover system information exposed by the firmware. It also sets the hardware name used in crash dumps, e.g.: Unable to handle kernel NULL pointer dereference at virtual address 00000000 pgd = ed3c0000 [00000000] *pgd=bf1f3835 Internal error: Oops: 817 [#1] SMP THUMB2 Modules linked in: CPU: 0 PID: 759 Comm: bash Not tainted 4.10.0-09601-g0e8f38792120-dirty #112 Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 ^^^ NOTE: This does *NOT* enable or encourage the use of DMI quirks, i.e., the the practice of identifying the platform via DMI to decide whether certain workarounds for buggy hardware and/or firmware need to be enabled. This would require the DMI subsystem to be enabled much earlier than we do on ARM, which is non-trivial. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Russell King <rmk+kernel@armlinux.org.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20170602135207.21708-14-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
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#
f14c66ce |
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20-Oct-2016 |
Ard Biesheuvel <ardb@kernel.org> |
arm64: mm: replace 'block_mappings_allowed' with 'page_mappings_only' In preparation of adding support for contiguous PTE and PMD mappings, let's replace 'block_mappings_allowed' with 'page_mappings_only', which will be a more accurate description of the nature of the setting once we add such contiguous mappings into the mix. Reviewed-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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#
74c102c9 |
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29-Jun-2016 |
Ard Biesheuvel <ardb@kernel.org> |
arm64: efi: avoid block mappings for unaligned UEFI memory regions When running the OS with a page size > 4 KB, we need to round up mappings for regions that are not aligned to the OS's page size. We already avoid block mappings for EfiRuntimeServicesCode/Data regions for other reasons, but in the unlikely event that other unaliged regions exists that have the EFI_MEMORY_RUNTIME attribute set, ensure that unaligned regions are always mapped down to pages. This way, the overlapping page is guaranteed not to be covered by a block mapping that needs to be split. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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#
bd264d04 |
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29-Jun-2016 |
Ard Biesheuvel <ardb@kernel.org> |
arm64: efi: always map runtime services code and data regions down to pages To avoid triggering diagnostics in the MMU code that are finicky about splitting block mappings into more granular mappings, ensure that regions that are likely to appear in the Memory Attributes table as well as the UEFI memory map are always mapped down to pages. This way, we can use apply_to_page_range() instead of create_pgd_mapping() for the second pass, which cannot split or merge block entries, and operates strictly on PTEs. Note that this aligns the arm64 Memory Attributes table handling code with the ARM code, which already uses apply_to_page_range() to set the strict permissions. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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#
53e1b329 |
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29-Jun-2016 |
Ard Biesheuvel <ardb@kernel.org> |
arm64: mm: add param to force create_pgd_mapping() to use page mappings Add a bool parameter 'allow_block_mappings' to create_pgd_mapping() and the various helper functions that it descends into, to give the caller control over whether block entries may be used to create the mapping. The UEFI runtime mapping routines will use this to avoid creating block entries that would need to split up into page entries when applying the permissions listed in the Memory Attributes firmware table. This also replaces the block_mappings_allowed() helper function that was added for DEBUG_PAGEALLOC functionality, but the resulting code is functionally equivalent (given that debug_page_alloc does not operate on EFI page table entries anyway) Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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#
57fdb89a |
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25-Apr-2016 |
Ard Biesheuvel <ardb@kernel.org> |
arm64/efi/libstub: Make screen_info accessible to the UEFI stub Unlike on 32-bit ARM, where we need to pass the stub's version of struct screen_info to the kernel proper via a configuration table, on 64-bit ARM it simply involves making the core kernel's copy of struct screen_info visible to the stub by exposing an __efistub_ alias for it. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Acked-by: Will Deacon <will.deacon@arm.com> Cc: Borislav Petkov <bp@alien8.de> Cc: David Herrmann <dh.herrmann@gmail.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Jones <pjones@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-21-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
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#
1fd55a9a |
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25-Apr-2016 |
Ard Biesheuvel <ardb@kernel.org> |
arm64/efi: Apply strict permissions to UEFI Runtime Services regions Recent UEFI versions expose permission attributes for runtime services memory regions, either in the UEFI memory map or in the separate memory attributes table. This allows the kernel to map these regions with stricter permissions, rather than the RWX permissions that are used by default. So wire this up in our mapping routine. Note that in the absence of permission attributes, we still only map regions of type EFI_RUNTIME_SERVICE_CODE with the executable bit set. Also, we base the mapping attributes of EFI_MEMORY_MAPPED_IO on the type directly rather than on the absence of the EFI_MEMORY_WB attribute. This is more correct, but is also required for compatibility with the upcoming support for the Memory Attributes Table, which only carries permission attributes, not memory type attributes. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Jones <pjones@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1461614832-17633-12-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
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#
f7d92489 |
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30-Nov-2015 |
Ard Biesheuvel <ardb@kernel.org> |
arm64/efi: refactor EFI init and runtime code for reuse by 32-bit ARM This refactors the EFI init and runtime code that will be shared between arm64 and ARM so that it can be built for both archs. Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
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#
e5bc22a4 |
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30-Nov-2015 |
Ard Biesheuvel <ardb@kernel.org> |
arm64/efi: split off EFI init and runtime code for reuse by 32-bit ARM This splits off the early EFI init and runtime code that - discovers the EFI params and the memory map from the FDT, and installs the memblocks and config tables. - prepares and installs the EFI page tables so that UEFI Runtime Services can be invoked at the virtual address installed by the stub. This will allow it to be reused for 32-bit ARM. Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
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#
4dffbfc4 |
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30-Nov-2015 |
Ard Biesheuvel <ardb@kernel.org> |
arm64/efi: mark UEFI reserved regions as MEMBLOCK_NOMAP Change the EFI memory reservation logic to use memblock_mark_nomap() rather than memblock_reserve() to mark UEFI reserved regions as occupied. In addition to reserving them against allocations done by memblock, this will also prevent them from being covered by the linear mapping. Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
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#
66362c9a |
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23-Nov-2015 |
Ard Biesheuvel <ardb@kernel.org> |
arm64: efi: fix initcall return values Even though initcall return values are typically ignored, the prototype is to return 0 on success or a negative errno value on error. So fix the arm_enable_runtime_services() implementation to return 0 on conditions that are not in fact errors, and return a meaningful error code otherwise. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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#
81d94577 |
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23-Nov-2015 |
Ard Biesheuvel <ardb@kernel.org> |
arm64: efi: deal with NULL return value of early_memremap() Add NULL return value checks to two invocations of early_memremap() in the UEFI init code. For the UEFI configuration tables, we just warn since we have a better chance of being able to report the issue in a way that can actually be noticed by a human operator if we don't abort right away. For the UEFI memory map, however, all we can do is panic() since we cannot proceed without a description of memory. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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#
3b12acf4 |
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23-Nov-2015 |
Mark Rutland <mark.rutland@arm.com> |
arm64: efi: correctly map runtime regions The kernel may use a page granularity of 4K, 16K, or 64K depending on configuration. When mapping EFI runtime regions, we use memrange_efi_to_native to round the physical base address of a region down to a kernel page boundary, and round the size up to a kernel page boundary, adding the residue left over from rounding down the physical base address. We do not round down the virtual base address. In __create_mapping we account for the offset of the virtual base from a granule boundary, adding the residue to the size before rounding the base down to said granule boundary. Thus we account for the residue twice, and when the residue is non-zero will cause __create_mapping to map an additional page at the end of the region. Depending on the memory map, this page may be in a region we are not intended/permitted to map, or may clash with a different region that we wish to map. In typical cases, mapping the next item in the memory map will overwrite the erroneously created entry, as we sort the memory map in the stub. As __create_mapping can cope with base addresses which are not page aligned, we can instead rely on it to map the region appropriately, and simplify efi_virtmap_init by removing the unnecessary code. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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#
65da0a8e |
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17-Nov-2015 |
Ard Biesheuvel <ardb@kernel.org> |
arm64: use non-global mappings for UEFI runtime regions As pointed out by Russell King in response to the proposed ARM version of this code, the sequence to switch between the UEFI runtime mapping and current's actual userland mapping (and vice versa) is potentially unsafe, since it leaves a time window between the switch to the new page tables and the TLB flush where speculative accesses may hit on stale global TLB entries. So instead, use non-global mappings, and perform the switch via the ordinary ASID-aware context switch routines. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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#
44511fb9 |
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23-Oct-2015 |
Ard Biesheuvel <ardb@kernel.org> |
efi: Use correct type for struct efi_memory_map::phys_map We have been getting away with using a void* for the physical address of the UEFI memory map, since, even on 32-bit platforms with 64-bit physical addresses, no truncation takes place if the memory map has been allocated by the firmware (which only uses 1:1 virtually addressable memory), which is usually the case. However, commit: 0f96a99dab36 ("efi: Add "efi_fake_mem" boot option") adds code that clones and modifies the UEFI memory map, and the clone may live above 4 GB on 32-bit platforms. This means our use of void* for struct efi_memory_map::phys_map has graduated from 'incorrect but working' to 'incorrect and broken', and we need to fix it. So redefine struct efi_memory_map::phys_map as phys_addr_t, and get rid of a bunch of casts that are now unneeded. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: izumi.taku@jp.fujitsu.com Cc: kamezawa.hiroyu@jp.fujitsu.com Cc: linux-efi@vger.kernel.org Cc: matt.fleming@intel.com Link: http://lkml.kernel.org/r/1445593697-1342-1-git-send-email-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
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#
7968c0e3 |
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26-Aug-2015 |
Leif Lindholm <leif.lindholm@linaro.org> |
efi/arm64: Clean up efi_get_fdt_params() interface As we now have a common debug infrastructure between core and arm64 efi, drop the bit of the interface passing verbose output flags around. Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Mark Salter <msalter@redhat.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
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#
c9494dc8 |
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26-Aug-2015 |
Leif Lindholm <leif.lindholm@linaro.org> |
arm64: Use core efi=debug instead of uefi_debug command line parameter Now that we have an efi=debug command line option in the core code, use this instead of the arm64-specific uefi_debug option. Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Mark Salter <msalter@redhat.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
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5aec715d |
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06-Oct-2015 |
Will Deacon <will@kernel.org> |
arm64: mm: rewrite ASID allocator and MM context-switching code Our current switch_mm implementation suffers from a number of problems: (1) The ASID allocator relies on IPIs to synchronise the CPUs on a rollover event (2) Because of (1), we cannot allocate ASIDs with interrupts disabled and therefore make use of a TIF_SWITCH_MM flag to postpone the actual switch to finish_arch_post_lock_switch (3) We run context switch with a reserved (invalid) TTBR0 value, even though the ASID and pgd are updated atomically (4) We take a global spinlock (cpu_asid_lock) during context-switch (5) We use h/w broadcast TLB operations when they are not required (e.g. in flush_context) This patch addresses these problems by rewriting the ASID algorithm to match the bitmap-based arch/arm/ implementation more closely. This in turn allows us to remove much of the complications surrounding switch_mm, including the ugly thread flag. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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8e63d388 |
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06-Oct-2015 |
Will Deacon <will@kernel.org> |
arm64: flush: use local TLB and I-cache invalidation There are a number of places where a single CPU is running with a private page-table and we need to perform maintenance on the TLB and I-cache in order to ensure correctness, but do not require the operation to be broadcast to other CPUs. This patch adds local variants of tlb_flush_all and __flush_icache_all to support these use-cases and updates the callers respectively. __local_flush_icache_all also implies an isb, since it is intended to be used synchronously. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: David Daney <david.daney@cavium.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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#
0ce3cc00 |
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25-Sep-2015 |
Ard Biesheuvel <ardb@kernel.org> |
arm64/efi: Fix boot crash by not padding between EFI_MEMORY_RUNTIME regions The new Properties Table feature introduced in UEFIv2.5 may split memory regions that cover PE/COFF memory images into separate code and data regions. Since these regions only differ in the type (runtime code vs runtime data) and the permission bits, but not in the memory type attributes (UC/WC/WT/WB), the spec does not require them to be aligned to 64 KB. Since the relative offset of PE/COFF .text and .data segments cannot be changed on the fly, this means that we can no longer pad out those regions to be mappable using 64 KB pages. Unfortunately, there is no annotation in the UEFI memory map that identifies data regions that were split off from a code region, so we must apply this logic to all adjacent runtime regions whose attributes only differ in the permission bits. So instead of rounding each memory region to 64 KB alignment at both ends, only round down regions that are not directly preceded by another runtime region with the same type attributes. Since the UEFI spec does not mandate that the memory map be sorted, this means we also need to sort it first. Note that this change will result in all EFI_MEMORY_RUNTIME regions whose start addresses are not aligned to the OS page size to be mapped with executable permissions (i.e., on kernels compiled with 64 KB pages). However, since these mappings are only active during the time that UEFI Runtime Services are being invoked, the window for abuse is rather small. Tested-by: Mark Salter <msalter@redhat.com> Tested-by: Mark Rutland <mark.rutland@arm.com> [UEFI 2.4 only] Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Reviewed-by: Mark Salter <msalter@redhat.com> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Cc: <stable@vger.kernel.org> # v4.0+ Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-kernel@vger.kernel.org Link: http://lkml.kernel.org/r/1443218539-7610-3-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
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#
f91b1fea |
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26-Jul-2015 |
Ard Biesheuvel <ardb@kernel.org> |
arm64/efi: map the entire UEFI vendor string before reading it At boot, the UTF-16 UEFI vendor string is copied from the system table into a char array with a size of 100 bytes. However, this size of 100 bytes is also used for memremapping() the source, which may not be sufficient if the vendor string exceeds 50 UTF-16 characters, and the placement of the vendor string inside a 4 KB page happens to leave the end unmapped. So use the correct '100 * sizeof(efi_char16_t)' for the size of the mapping. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Fixes: f84d02755f5a ("arm64: add EFI runtime services") Cc: <stable@vger.kernel.org> # 3.16+ Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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#
ad5fb870 |
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02-Apr-2015 |
Dan Williams <dan.j.williams@intel.com> |
e820, efi: add ACPI 6.0 persistent memory types ACPI 6.0 formalizes e820-type-7 and efi-type-14 as persistent memory. Mark it "reserved" and allow it to be claimed by a persistent memory device driver. This definition is in addition to the Linux kernel's existing type-12 definition that was recently added in support of shipping platforms with NVDIMM support that predate ACPI 6.0 (which now classifies type-12 as OEM reserved). Note, /proc/iomem can be consulted for differentiating legacy "Persistent Memory (legacy)" E820_PRAM vs standard "Persistent Memory" E820_PMEM. Cc: Boaz Harrosh <boaz@plexistor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jens Axboe <axboe@fb.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matthew Wilcox <willy@linux.intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Acked-by: Jeff Moyer <jmoyer@redhat.com> Acked-by: Andy Lutomirski <luto@amacapital.net> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Acked-by: Christoph Hellwig <hch@lst.de> Tested-by: Toshi Kani <toshi.kani@hp.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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130c93fd |
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19-Mar-2015 |
Will Deacon <will@kernel.org> |
arm64: efi: don't restore TTBR0 if active_mm points at init_mm init_mm isn't a normal mm: it has swapper_pg_dir as its pgd (which contains kernel mappings) and is used as the active_mm for the idle thread. When restoring the pgd after an EFI call, we write current->active_mm into TTBR0. If the current task is actually the idle thread (e.g. when initialising the EFI RTC before entering userspace), then the TLB can erroneously populate itself with junk global entries as a result of speculative table walks. When we do eventually return to userspace, the task can end up hitting these junk mappings leading to lockups, corruption or crashes. This patch fixes the problem in the same way as the CPU suspend code by ensuring that we never switch to the init_mm in efi_set_pgd and instead point TTBR0 at the zero page. A check is also added to cpu_switch_mm to BUG if we get passed swapper_pg_dir. Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Fixes: f3cdfd239da5 ("arm64/efi: move SetVirtualAddressMap() to UEFI stub") Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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#
60c0d45a |
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06-Mar-2015 |
Ard Biesheuvel <ardb@kernel.org> |
efi/arm64: use UEFI for system reset and poweroff If UEFI Runtime Services are available, they are preferred over direct PSCI calls or other methods to reset the system. For the reset case, we need to hook into machine_restart(), as the arm_pm_restart function pointer may be overwritten by modules. Tested-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Matt Fleming <matt.fleming@intel.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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#
60305db9 |
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22-Jan-2015 |
Ard Biesheuvel <ard.biesheuvel-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org> |
arm64/efi: move virtmap init to early initcall Now that the create_mapping() code in mm/mmu.c is able to support setting up kernel page tables at initcall time, we can move the whole virtmap creation to arm64_enable_runtime_services() instead of having a distinct stage during early boot. This also allows us to drop the arm64-specific EFI_VIRTMAP flag. Signed-off-by: Ard Biesheuvel <ard.biesheuvel-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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7fe5d2b1 |
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14-Jan-2015 |
Ard Biesheuvel <ardb@kernel.org> |
arm64/efi: handle potential failure to remap memory map When remapping the UEFI memory map using ioremap_cache(), we have to deal with potential failure. Note that, even if the common case is for ioremap_cache() to return the existing linear mapping of the memory map, we cannot rely on that to be always the case, e.g., in the presence of a mem= kernel parameter. At the same time, remove a stale comment and move the memmap code together. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Mark Salter <msalter@redhat.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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9679be10 |
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20-Oct-2014 |
Ard Biesheuvel <ardb@kernel.org> |
arm64/efi: remove idmap manipulations from UEFI code Now that we have moved the call to SetVirtualAddressMap() to the stub, UEFI has no use for the ID map, so we can drop the code that installs ID mappings for UEFI memory regions. Acked-by: Leif Lindholm <leif.lindholm@linaro.org> Acked-by: Will Deacon <will.deacon@arm.com> Tested-by: Leif Lindholm <leif.lindholm@linaro.org> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
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3033b845 |
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20-Oct-2014 |
Ard Biesheuvel <ardb@kernel.org> |
arm64/efi: remove free_boot_services() and friends Now that we are calling SetVirtualAddressMap() from the stub, there is no need to reserve boot-only memory regions, which implies that there is also no reason to free them again later. Acked-by: Leif Lindholm <leif.lindholm@linaro.org> Acked-by: Will Deacon <will.deacon@arm.com> Tested-by: Leif Lindholm <leif.lindholm@linaro.org> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
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f3cdfd23 |
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20-Oct-2014 |
Ard Biesheuvel <ardb@kernel.org> |
arm64/efi: move SetVirtualAddressMap() to UEFI stub In order to support kexec, the kernel needs to be able to deal with the state of the UEFI firmware after SetVirtualAddressMap() has been called. To avoid having separate code paths for non-kexec and kexec, let's move the call to SetVirtualAddressMap() to the stub: this will guarantee us that it will only be called once (since the stub is not executed during kexec), and ensures that the UEFI state is identical between kexec and normal boot. This implies that the layout of the virtual mapping needs to be created by the stub as well. All regions are rounded up to a naturally aligned multiple of 64 KB (for compatibility with 64k pages kernels) and recorded in the UEFI memory map. The kernel proper reads those values and installs the mappings in a dedicated set of page tables that are swapped in during UEFI Runtime Services calls. Acked-by: Leif Lindholm <leif.lindholm@linaro.org> Acked-by: Matt Fleming <matt.fleming@intel.com> Tested-by: Leif Lindholm <leif.lindholm@linaro.org> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
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0e63ea48 |
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08-Jan-2015 |
Ard Biesheuvel <ardb@kernel.org> |
arm64/efi: add missing call to early_ioremap_reset() The early ioremap support introduced by patch bf4b558eba92 ("arm64: add early_ioremap support") failed to add a call to early_ioremap_reset() at an appropriate time. Without this call, invocations of early_ioremap etc. that are done too late will go unnoticed and may cause corruption. This is exactly what happened when the first user of this feature was added in patch f84d02755f5a ("arm64: add EFI runtime services"). The early mapping of the EFI memory map is unmapped during an early initcall, at which time the early ioremap support is long gone. Fix by adding the missing call to early_ioremap_reset() to setup_arch(), and move the offending early_memunmap() to right after the point where the early mapping of the EFI memory map is last used. Fixes: f84d02755f5a ("arm64: add EFI runtime services") Cc: <stable@vger.kernel.org> Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
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#
b07bfaa3 |
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15-Oct-2014 |
Ard Biesheuvel <ardb@kernel.org> |
arm64: dmi: set DMI string as dump stack arch description This sets the DMI string, containing system type, serial number, firmware version etc. as dump stack arch description, so that oopses and other kernel stack dumps automatically have this information included, if available. Tested-by: Leif Lindholm <leif.lindholm@linaro.org> Acked-by: Leif Lindholm <leif.lindholm@linaro.org> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
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#
d1ae8c00 |
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04-Oct-2014 |
Yi Li <yi.li@linaro.org> |
arm64: dmi: Add SMBIOS/DMI support SMBIOS is important for server hardware vendors. It implements a spec for providing descriptive information about the platform. Things like serial numbers, physical layout of the ports, build configuration data, and the like. Signed-off-by: Yi Li <yi.li@linaro.org> Tested-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Tested-by: Leif Lindholm <leif.lindholm@linaro.org> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
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#
4e27d475 |
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16-Oct-2014 |
Ard Biesheuvel <ardb@kernel.org> |
arm64/efi: drop redundant set_bit(EFI_CONFIG_TABLES) The EFI_CONFIG_TABLES bit already gets set by efi_config_init(), so there is no reason to set it again after this function returns successfully. Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
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61139eb0 |
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20-Oct-2014 |
Ard Biesheuvel <ardb@kernel.org> |
arm64/efi: invert UEFI memory region reservation logic Instead of reserving the memory regions based on which types we know need to be reserved, consider only regions of the following types as free for general use by the OS: EFI_LOADER_CODE EFI_LOADER_DATA EFI_BOOT_SERVICES_CODE EFI_BOOT_SERVICES_DATA EFI_CONVENTIONAL_MEMORY Note that this also fixes a problem with the original code, which would misidentify a EFI_RUNTIME_SERVICES_DATA region as not reserved if it does not have the EFI_MEMORY_RUNTIME attribute set. However, it is perfectly legal for the firmware not to request a virtual mapping for EFI_RUNTIME_SERVICES_DATA regions that contain configuration tables, in which case the EFI_MEMORY_RUNTIME attribute would not be set. Acked-by: Roy Franz <roy.franz@linaro.org> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
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#
65ba758f |
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03-Sep-2014 |
Laszlo Ersek <lersek@redhat.com> |
arm64: efi: Format EFI memory type & attrs with efi_md_typeattr_format() An example log excerpt demonstrating the change: Before the patch: > Processing EFI memory map: > 0x000040000000-0x000040000fff [Loader Data] > 0x000040001000-0x00004007ffff [Conventional Memory] > 0x000040080000-0x00004072afff [Loader Data] > 0x00004072b000-0x00005fdfffff [Conventional Memory] > 0x00005fe00000-0x00005fe0ffff [Loader Data] > 0x00005fe10000-0x0000964e8fff [Conventional Memory] > 0x0000964e9000-0x0000964e9fff [Loader Data] > 0x0000964ea000-0x000096c52fff [Loader Code] > 0x000096c53000-0x00009709dfff [Boot Code]* > 0x00009709e000-0x0000970b3fff [Runtime Code]* > 0x0000970b4000-0x0000970f4fff [Runtime Data]* > 0x0000970f5000-0x000097117fff [Runtime Code]* > 0x000097118000-0x000097199fff [Runtime Data]* > 0x00009719a000-0x0000971dffff [Runtime Code]* > 0x0000971e0000-0x0000997f8fff [Conventional Memory] > 0x0000997f9000-0x0000998f1fff [Boot Data]* > 0x0000998f2000-0x0000999eafff [Conventional Memory] > 0x0000999eb000-0x00009af09fff [Boot Data]* > 0x00009af0a000-0x00009af21fff [Conventional Memory] > 0x00009af22000-0x00009af46fff [Boot Data]* > 0x00009af47000-0x00009af5bfff [Conventional Memory] > 0x00009af5c000-0x00009afe1fff [Boot Data]* > 0x00009afe2000-0x00009afe2fff [Conventional Memory] > 0x00009afe3000-0x00009c01ffff [Boot Data]* > 0x00009c020000-0x00009efbffff [Conventional Memory] > 0x00009efc0000-0x00009f14efff [Boot Code]* > 0x00009f14f000-0x00009f162fff [Runtime Code]* > 0x00009f163000-0x00009f194fff [Runtime Data]* > 0x00009f195000-0x00009f197fff [Boot Data]* > 0x00009f198000-0x00009f198fff [Runtime Data]* > 0x00009f199000-0x00009f1acfff [Conventional Memory] > 0x00009f1ad000-0x00009f1affff [Boot Data]* > 0x00009f1b0000-0x00009f1b0fff [Runtime Data]* > 0x00009f1b1000-0x00009fffffff [Boot Data]* > 0x000004000000-0x000007ffffff [Memory Mapped I/O] > 0x000009010000-0x000009010fff [Memory Mapped I/O] After the patch: > Processing EFI memory map: > 0x000040000000-0x000040000fff [Loader Data | | | | | |WB|WT|WC|UC] > 0x000040001000-0x00004007ffff [Conventional Memory| | | | | |WB|WT|WC|UC] > 0x000040080000-0x00004072afff [Loader Data | | | | | |WB|WT|WC|UC] > 0x00004072b000-0x00005fdfffff [Conventional Memory| | | | | |WB|WT|WC|UC] > 0x00005fe00000-0x00005fe0ffff [Loader Data | | | | | |WB|WT|WC|UC] > 0x00005fe10000-0x0000964e8fff [Conventional Memory| | | | | |WB|WT|WC|UC] > 0x0000964e9000-0x0000964e9fff [Loader Data | | | | | |WB|WT|WC|UC] > 0x0000964ea000-0x000096c52fff [Loader Code | | | | | |WB|WT|WC|UC] > 0x000096c53000-0x00009709dfff [Boot Code | | | | | |WB|WT|WC|UC]* > 0x00009709e000-0x0000970b3fff [Runtime Code |RUN| | | | |WB|WT|WC|UC]* > 0x0000970b4000-0x0000970f4fff [Runtime Data |RUN| | | | |WB|WT|WC|UC]* > 0x0000970f5000-0x000097117fff [Runtime Code |RUN| | | | |WB|WT|WC|UC]* > 0x000097118000-0x000097199fff [Runtime Data |RUN| | | | |WB|WT|WC|UC]* > 0x00009719a000-0x0000971dffff [Runtime Code |RUN| | | | |WB|WT|WC|UC]* > 0x0000971e0000-0x0000997f8fff [Conventional Memory| | | | | |WB|WT|WC|UC] > 0x0000997f9000-0x0000998f1fff [Boot Data | | | | | |WB|WT|WC|UC]* > 0x0000998f2000-0x0000999eafff [Conventional Memory| | | | | |WB|WT|WC|UC] > 0x0000999eb000-0x00009af09fff [Boot Data | | | | | |WB|WT|WC|UC]* > 0x00009af0a000-0x00009af21fff [Conventional Memory| | | | | |WB|WT|WC|UC] > 0x00009af22000-0x00009af46fff [Boot Data | | | | | |WB|WT|WC|UC]* > 0x00009af47000-0x00009af5bfff [Conventional Memory| | | | | |WB|WT|WC|UC] > 0x00009af5c000-0x00009afe1fff [Boot Data | | | | | |WB|WT|WC|UC]* > 0x00009afe2000-0x00009afe2fff [Conventional Memory| | | | | |WB|WT|WC|UC] > 0x00009afe3000-0x00009c01ffff [Boot Data | | | | | |WB|WT|WC|UC]* > 0x00009c020000-0x00009efbffff [Conventional Memory| | | | | |WB|WT|WC|UC] > 0x00009efc0000-0x00009f14efff [Boot Code | | | | | |WB|WT|WC|UC]* > 0x00009f14f000-0x00009f162fff [Runtime Code |RUN| | | | |WB|WT|WC|UC]* > 0x00009f163000-0x00009f194fff [Runtime Data |RUN| | | | |WB|WT|WC|UC]* > 0x00009f195000-0x00009f197fff [Boot Data | | | | | |WB|WT|WC|UC]* > 0x00009f198000-0x00009f198fff [Runtime Data |RUN| | | | |WB|WT|WC|UC]* > 0x00009f199000-0x00009f1acfff [Conventional Memory| | | | | |WB|WT|WC|UC] > 0x00009f1ad000-0x00009f1affff [Boot Data | | | | | |WB|WT|WC|UC]* > 0x00009f1b0000-0x00009f1b0fff [Runtime Data |RUN| | | | |WB|WT|WC|UC]* > 0x00009f1b1000-0x00009fffffff [Boot Data | | | | | |WB|WT|WC|UC]* > 0x000004000000-0x000007ffffff [Memory Mapped I/O |RUN| | | | | | | |UC] > 0x000009010000-0x000009010fff [Memory Mapped I/O |RUN| | | | | | | |UC] The attribute bitmap is now displayed, in decoded form. Signed-off-by: Laszlo Ersek <lersek@redhat.com> Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
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6632210f |
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17-Aug-2014 |
Dave Young <dyoung@redhat.com> |
arm64/efi: Do not enter virtual mode if booting with efi=noruntime or noefi In case efi runtime disabled via noefi kernel cmdline arm64_enter_virtual_mode should error out. At the same time move early_memunmap(memmap.map, mapsize) to the beginning of the function or it will leak early mem. Signed-off-by: Dave Young <dyoung@redhat.com> Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
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88f8abd5 |
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14-Aug-2014 |
Dave Young <dyoung@redhat.com> |
arm64/efi: uefi_init error handling fix There's one early memmap leak in uefi_init error path, fix it and slightly tune the error handling code. Signed-off-by: Dave Young <dyoung@redhat.com> Acked-by: Mark Salter <msalter@redhat.com> Reported-by: Will Deacon <will.deacon@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
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6f325eaa |
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22-Sep-2014 |
Catalin Marinas <catalin.marinas@arm.com> |
Revert "arm64: dmi: Add SMBIOS/DMI support" This reverts commit 668ebd106860f09f43993517f786a2ddfd0f9ebe. ... because of lots of warnings during boot if Linux isn't started as an EFI application: WARNING: CPU: 4 PID: 1 at /work/Linux/linux-2.6-aarch64/drivers/firmware/dmi_scan.c:591 dmi_matches+0x10c/0x110() dmi check: not initialized yet. Modules linked in: CPU: 4 PID: 1 Comm: swapper/0 Not tainted 3.17.0-rc4+ #606 Call trace: [<ffffffc000087fb0>] dump_backtrace+0x0/0x124 [<ffffffc0000880e4>] show_stack+0x10/0x1c [<ffffffc0004d58f8>] dump_stack+0x74/0xb8 [<ffffffc0000ab640>] warn_slowpath_common+0x8c/0xb4 [<ffffffc0000ab6b4>] warn_slowpath_fmt+0x4c/0x58 [<ffffffc0003f2d7c>] dmi_matches+0x108/0x110 [<ffffffc0003f2da8>] dmi_check_system+0x24/0x68 [<ffffffc0006974c4>] atkbd_init+0x10/0x34 [<ffffffc0000814ac>] do_one_initcall+0x88/0x1a0 [<ffffffc00067aab4>] kernel_init_freeable+0x148/0x1e8 [<ffffffc0004d2c64>] kernel_init+0x10/0xd4 Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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668ebd10 |
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22-Sep-2014 |
Yi Li <yi.li@linaro.org> |
arm64: dmi: Add SMBIOS/DMI support SMBIOS is important for server hardware vendors. It implements a spec for providing descriptive information about the platform. Things like serial numbers, physical layout of the ports, build configuration data, and the like. This has been tested by dmidecode and lshw tools. This patch adds the call to dmi_scan_machine() to arm64_enter_virtual_mode(), as that is the point where the EFI Configuration Tables are registered as being available. It needs to be in an early_initcall anyway as dmi_id_init(), which is an arch_initcall itself, depends on dmi_scan_machine() having been called already. Signed-off-by: Yi Li <yi.li@linaro.org> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
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6a7519e8 |
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15-Aug-2014 |
Semen Protsenko <semen.protsenko@linaro.org> |
efi/arm64: Store Runtime Services revision "efi" global data structure contains "runtime_version" field which must be assigned in order to use it later in Runtime Services virtual calls (virt_efi_* functions). Before this patch "runtime_version" was unassigned (0), so each Runtime Service virtual call that checks revision would fail. Signed-off-by: Semen Protsenko <semen.protsenko@linaro.org> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: <stable@vger.kernel.org> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
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#
86c8b27a |
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28-Jul-2014 |
Leif Lindholm <leif.lindholm@linaro.org> |
arm64: ignore DT memreserve entries when booting in UEFI mode UEFI provides its own method for marking regions to reserve, via the memory map which is also used to initialise memblock. So when using the UEFI memory map, ignore any memreserve entries present in the DT. Reported-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
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99a5603e |
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04-Jul-2014 |
Ard Biesheuvel <ardb@kernel.org> |
efi/arm64: Handle missing virtual mapping for UEFI System Table If we cannot resolve the virtual address of the UEFI System Table, its physical offset must be missing from the virtual memory map, and there is really no point in proceeding with installing the virtual memory map and the runtime services dispatch table. So back out gracefully. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Mark Salter <msalter@redhat.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
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e15dd494 |
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04-Jul-2014 |
Ard Biesheuvel <ardb@kernel.org> |
efi/arm64: Preserve FP/SIMD registers on UEFI runtime services calls According to the UEFI spec section 2.3.6.4, the use of FP/SIMD instructions is allowed, and should adhere to the AAPCS64 calling convention, which states that 'only the bottom 64 bits of each value stored in registers v8-v15 need to be preserved' (section 5.1.2). This applies equally to UEFI Runtime Services called by the kernel, so make sure the FP/SIMD register file is preserved in this case. We do this by enabling the wrappers for UEFI Runtime Services (CONFIG_EFI_RUNTIME_WRAPPERS) and inserting calls to kernel_neon_begin()and kernel_neon_end() into these wrappers. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
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74bcc249 |
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23-May-2014 |
Leif Lindholm <leif.lindholm@linaro.org> |
arm64: efi: only attempt efi map setup if booting via EFI Booting a kernel with CONFIG_EFI enabled on a non-EFI system caused an oops with the current UEFI support code. Add the required test to prevent this. Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
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f84d0275 |
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15-Apr-2014 |
Mark Salter <msalter@redhat.com> |
arm64: add EFI runtime services This patch adds EFI runtime support for arm64. This runtime support allows the kernel to access various EFI runtime services provided by EFI firmware. Things like reboot, real time clock, EFI boot variables, and others. This functionality is supported for little endian kernels only. The UEFI firmware standard specifies that the firmware be little endian. A future patch is expected to add support for big endian kernels running with little endian firmware. Signed-off-by: Mark Salter <msalter@redhat.com> [ Remove unnecessary cache/tlb maintenance. ] Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
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