x86/cpu: Move cpu_core_id into topology info

Rename it to core_id and stick it to the other ID fields.

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230814085112.566519388@linutronix.de

x86/cpu: Move phys_proc_id into topology info

Rename it to pkg_id which is the terminology used in the kernel.

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230814085112.329006989@linutronix.de

x86/cpu: Encapsulate topology information in cpuinfo_x86

The topology related information is randomly scattered across cpuinfo_x86.

Create a new structure cpuinfo_topo and move in a first step initial_apicid
and apicid into it.

Aside of being better readable this is in preparation for replacing the
horribly fragile CPU topology evaluation code further down the road.

Consolidate APIC ID fields to u32 as that represents the hardware type.

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230814085112.269787744@linutronix.de

x86: Expose thread features in /proc/$PID/status

Applications and loaders can have logic to decide whether to enable
shadow stack. They usually don't report whether shadow stack has been
enabled or not, so there is no way to verify whether an application
actually is protected by shadow stack.

Add two lines in /proc/$PID/status to report enabled and locked features.

Since, this involves referring to arch specific defines in asm/prctl.h,
implement an arch breakout to emit the feature lines.

[Switched to CET, added to commit log]

Co-developed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
Tested-by: Pengfei Xu <pengfei.xu@intel.com>
Tested-by: John Allen <john.allen@amd.com>
Tested-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/all/20230613001108.3040476-37-rick.p.edgecombe%40intel.com

x86/aperfmperf: Integrate the fallback code from show_cpuinfo()

Due to the avoidance of IPIs to idle CPUs arch_freq_get_on_cpu() can return
0 when the last sample was too long ago.

show_cpuinfo() has a fallback to cpufreq_quick_get() and if that fails to
return cpu_khz, but the readout code for the per CPU scaling frequency in
sysfs does not.

Move that fallback into arch_freq_get_on_cpu() so the behaviour is the same
when reading /proc/cpuinfo and /sys/..../cur_scaling_freq.

Suggested-by: "Rafael J. Wysocki" <rafael@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Doug Smythies <dsmythies@telus.net>
Link: https://lore.kernel.org/r/87pml5180p.ffs@tglx

x86/aperfmperf: Replace arch_freq_get_on_cpu()

Reading the current CPU frequency from /sys/..../scaling_cur_freq involves
in the worst case two IPIs due to the ad hoc sampling.

The frequency invariance infrastructure provides the APERF/MPERF samples
already. Utilize them and consolidate this with the /proc/cpuinfo readout.

The sample is considered valid for 20ms. So for idle or isolated NOHZ full
CPUs the function returns 0, which is matching the previous behaviour.

The resulting text size vs. the original APERF/MPERF plus the separate
frequency invariance code:

text: 2411 -> 723
init.text: 0 -> 767

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/20220415161206.934040006@linutronix.de

x86/cpu: Print VMX flags in /proc/cpuinfo using VMX_FEATURES_*

Add support for generating VMX feature names in capflags.c and use the
resulting x86_vmx_flags to print the VMX flags in /proc/cpuinfo. Don't
print VMX flags if no bits are set in word 0, which holds Pin Controls.
Pin Control's INTR and NMI exiting are fundamental pillars of VMX, if
they are not supported then the CPU is broken, it does not actually
support VMX, or the kernel wasn't built with support for the target CPU.

Print the features in a dedicated "vmx flags" line to avoid polluting
the common "flags" and to avoid having to prefix all flags with "vmx_",
which results in horrendously long names.

Keep synthetic VMX flags in cpufeatures to preserve /proc/cpuinfo's ABI
for those flags. This means that "flags" and "vmx flags" will have
duplicate entries for tpr_shadow (virtual_tpr), vnmi, ept, flexpriority,
vpid and ept_ad, but caps the pollution of "flags" at those six VMX
features. The vendor-specific code that populates the synthetic flags
will be consolidated in a future patch to further minimize the lasting
damage.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20191221044513.21680-12-sean.j.christopherson@intel.com

x86: Convert some slow-path static_cpu_has() callers to boot_cpu_has()

Using static_cpu_has() is pointless on those paths, convert them to the
boot_cpu_has() variant.

No functional changes.

Reported-by: Nadav Amit <nadav.amit@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Rik van Riel <riel@surriel.com>
Reviewed-by: Juergen Gross <jgross@suse.com> # for paravirt
Cc: Aubrey Li <aubrey.li@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Thomas Lendacky <Thomas.Lendacky@amd.com>
Cc: linux-edac@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: virtualization@lists.linux-foundation.org
Cc: x86@kernel.org
Link: https://lkml.kernel.org/r/20190330112022.28888-3-bp@alien8.de

x86/cpu: Change type of x86_cache_size variable to unsigned int

Currently, x86_cache_size is of type int, which makes no sense as we
will never have a valid cache size equal or less than 0. So instead of
initializing this variable to -1, it can perfectly be initialized to 0
and use it as an unsigned variable instead.

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Addresses-Coverity-ID: 1464429
Link: http://lkml.kernel.org/r/20180213192208.GA26414@embeddedor.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

x86/cpu: Rename cpu_data.x86_mask to cpu_data.x86_stepping

x86_mask is a confusing name which is hard to associate with the
processor's stepping.

Additionally, correct an indent issue in lib/cpu.c.

Signed-off-by: Jia Zhang <qianyue.zj@alibaba-inc.com>
[ Updated it to more recent kernels. ]
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bp@alien8.de
Cc: tony.luck@intel.com
Link: http://lkml.kernel.org/r/1514771530-70829-1-git-send-email-qianyue.zj@alibaba-inc.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

x86 / CPU: Always show current CPU frequency in /proc/cpuinfo

After commit 890da9cf0983 (Revert "x86: do not use cpufreq_quick_get()
for /proc/cpuinfo "cpu MHz"") the "cpu MHz" number in /proc/cpuinfo
on x86 can be either the nominal CPU frequency (which is constant)
or the frequency most recently requested by a scaling governor in
cpufreq, depending on the cpufreq configuration. That is somewhat
inconsistent and is different from what it was before 4.13, so in
order to restore the previous behavior, make it report the current
CPU frequency like the scaling_cur_freq sysfs file in cpufreq.

To that end, modify the /proc/cpuinfo implementation on x86 to use
aperfmperf_snapshot_khz() to snapshot the APERF and MPERF feedback
registers, if available, and use their values to compute the CPU
frequency to be reported as "cpu MHz".

However, do that carefully enough to avoid accumulating delays that
lead to unacceptable access times for /proc/cpuinfo on systems with
many CPUs. Run aperfmperf_snapshot_khz() once on all CPUs
asynchronously at the /proc/cpuinfo open time, add a single delay
upfront (if necessary) at that point and simply compute the current
frequency while running show_cpuinfo() for each individual CPU.

Also, to avoid slowing down /proc/cpuinfo accesses too much, reduce
the default delay between consecutive APERF and MPERF reads to 10 ms,
which should be sufficient to get large enough numbers for the
frequency computation in all cases.

Fixes: 890da9cf0983 (Revert "x86: do not use cpufreq_quick_get() for /proc/cpuinfo "cpu MHz"")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ingo Molnar <mingo@kernel.org>

Revert "x86: CPU: Fix up "cpu MHz" in /proc/cpuinfo"

This reverts commit 941f5f0f6ef5338814145cf2b813cf1f98873e2f.

Sadly, it turns out that we really can't just do the cross-CPU IPI to
all CPU's to get their proper frequencies, because it's much too
expensive on systems with lots of cores.

So we'll have to revert this for now, and revisit it using a smarter
model (probably doing one system-wide IPI at open time, and doing all
the frequency calculations in parallel).

Reported-by: WANG Chao <chao.wang@ucloud.cn>
Reported-by: Ingo Molnar <mingo@kernel.org>
Cc: Rafael J Wysocki <rafael.j.wysocki@intel.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

x86: CPU: Fix up "cpu MHz" in /proc/cpuinfo

Commit 890da9cf0983 (Revert "x86: do not use cpufreq_quick_get() for
/proc/cpuinfo "cpu MHz"") is not sufficient to restore the previous
behavior of "cpu MHz" in /proc/cpuinfo on x86 due to some changes
made after the commit it has reverted.

To address this, make the code in question use arch_freq_get_on_cpu()
which also is used by cpufreq for reporting the current frequency of
CPUs and since that function doesn't really depend on cpufreq in any
way, drop the CONFIG_CPU_FREQ dependency for the object file
containing it.

Also refactor arch_freq_get_on_cpu() somewhat to avoid IPIs and
return cached values right away if it is called very often over a
short time (to prevent user space from triggering IPI storms through
it).

Fixes: 890da9cf0983 (Revert "x86: do not use cpufreq_quick_get() for /proc/cpuinfo "cpu MHz"")
Cc: stable@kernel.org # 4.13 - together with 890da9cf0983
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Revert "x86: do not use cpufreq_quick_get() for /proc/cpuinfo "cpu MHz""

This reverts commit 51204e0639c49ada02fd823782ad673b6326d748.

There wasn't really any good reason for it, and people are complaining
(rightly) that it broke existing practice.

Cc: Len Brown <len.brown@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86: do not use cpufreq_quick_get() for /proc/cpuinfo "cpu MHz"

cpufreq_quick_get() allows cpufreq drivers to over-ride cpu_khz
that is otherwise reported in x86 /proc/cpuinfo "cpu MHz".

There are four problems with this scheme,
any of them is sufficient justification to delete it.

1. Depending on which cpufreq driver is loaded, the behavior
of this field is different.

2. Distros complain that they have to explain to users
why and how this field changes. Distros have requested a constant.

3. The two major providers of this information, acpi_cpufreq
and intel_pstate, both "get it wrong" in different ways.

acpi_cpufreq lies to the user by telling them that
they are running at whatever frequency was last
requested by software.

intel_pstate lies to the user by telling them that
they are running at the average frequency computed
over an undefined measurement. But an average computed
over an undefined interval, is itself, undefined...

4. On modern processors, user space utilities, such as
turbostat(1), are more accurate and more precise, while
supporing concurrent measurement over arbitrary intervals.

Users who have been consulting /proc/cpuinfo to
track changing CPU frequency will be dissapointed that
it no longer wiggles -- perhaps being unaware of the
limitations of the information they have been consuming.

Yes, they can change their scripts to look in sysfs
cpufreq/scaling_cur_frequency. Here they will find the same
data of dubious quality here removed from /proc/cpuinfo.
The value in sysfs will be addressed in a subsequent patch
to address issues 1-3, above.

Issue 4 will remain -- users that really care about
accurate frequency information should not be using either
proc or sysfs kernel interfaces.
They should be using using turbostat(8), or a similar
purpose-built analysis tool.

Signed-off-by: Len Brown <len.brown@intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

x86/cpu: Drop wp_works_ok member of struct cpuinfo_x86

Remove the wp_works_ok member of struct cpuinfo_x86. It's an
optimization back from Linux v0.99 times where we had no fixup support
yet and did the CR0.WP test via special code in the page fault handler.
The < 0 test was an optimization to not do the special casing for each
NULL ptr access violation but just for the first one doing the WP test.
Today it serves no real purpose as the test no longer needs special code
in the page fault handler and the only call side -- mem_init() -- calls
it just once, anyway. However, Xen pre-initializes it to 1, to skip the
test.

Doing the test again for Xen should be no issue at all, as even the
commit introducing skipping the test (commit d560bc61575e ("x86, xen:
Suppress WP test on Xen")) mentioned it being ban aid only. And, in
fact, testing the patch on Xen showed nothing breaks.

The pre-fixup times are long gone and with the removal of the fallback
handling code in commit a5c2a893dbd4 ("x86, 386 removal: Remove
CONFIG_X86_WP_WORKS_OK") the kernel requires a working CR0.WP anyway.
So just get rid of the "optimization" and do the test unconditionally.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Arnd Hannemann <hannemann@nets.rwth-aachen.de>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: "David S. Miller" <davem@davemloft.net>
Link: http://lkml.kernel.org/r/1486933932-585-3-git-send-email-minipli@googlemail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

x86: Replace cpu_**_mask() with topology_**_cpumask()

The former duplicate the functionalities of the latter but are
neither documented nor arch-independent.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Benoit Cousson <bcousson@baylibre.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Jean Delvare <jdelvare@suse.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Drokin <oleg.drokin@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Link: http://lkml.kernel.org/r/1432645896-12588-9-git-send-email-bgolaszewski@baylibre.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

x86: Replace seq_printf() with seq_puts()

seq_puts is a lot cheaper than seq_printf, so use that to print
literal strings.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Link: http://lkml.kernel.org/r/1417208622-12264-1-git-send-email-linux@rasmusvillemoes.dk
Signed-off-by: Ingo Molnar <mingo@kernel.org>

x86/cpufeature: Add bug flags to /proc/cpuinfo

Dump the flags which denote we have detected and/or have applied bug
workarounds to the CPU we're executing on, in a similar manner to the
feature flags.

The advantage is that those are not accumulating over time like the CPU
features.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1403609105-8332-2-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

x86/cpu: Always print SMP information in /proc/cpuinfo

Currently show_cpuinfo_core() displays cpu core information only if
the number of threads per a whole cores is 2 or larger.

However, this condition doesn't care about the number of
sockets. For example, this condition doesn't hold on systems
with two logical cpus consisting of two sockets and a single
core on each socket - yet the topology information would be
interesting to see in that case as well.

I don't know whether or not there are processors in real world
by which such configurations are possible, but at least on
vitual machine environments, such configuration can occur,
typically when no explicit SMP information is provided in
advance.

For example, on qemu/KVM, SMP information is specified via -smp
command-line option, more specifically, its syntax is:

-smp n[,cores=cores][,threads=threads][,sockets=sockets][,maxcpus=maxcpus]

If this is not specified, qemu tells configuration with
n-sockets, 1-core and 1-thread to the guest machine, on which
guest, MP information is not displayed in /proc/cpuinfo.

I saw this situation on VMWare guest environment, too.

To fix this issue, this patch simply removes the condition
because this information is useful even if there's only 1
thread.

Signed-off-by: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/5277D644.4090707@jp.fujitsu.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

x86: Get rid of ->hard_math and all the FPU asm fu

Reimplement FPU detection code in C and drop old, not-so-recommended
detection method in asm. Move all the relevant stuff into i387.c where
it conceptually belongs. Finally drop cpuinfo_x86.hard_math.

[ hpa: huge thanks to Borislav for taking my original concept patch
and productizing it ]

[ Boris, note to self: do not use static_cpu_has before alternatives! ]

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/1367244262-29511-2-git-send-email-bp@alien8.de
Link: http://lkml.kernel.org/r/1365436666-9837-2-git-send-email-bp@alien8.de
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

x86, cpu: Convert Cyrix coma bug detection

... to the new facility.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1363788448-31325-5-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

x86, cpu: Convert FDIV bug detection

... to the new facility. Add a reference to the wikipedia article
explaining the FDIV test we're doing here.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1363788448-31325-4-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

x86, cpu: Convert F00F bug detection

... to using the new facility and drop the cpuinfo_x86 member.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1363788448-31325-3-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

x86 idle: remove 32-bit-only "no-hlt" parameter, hlt_works_ok flag

Remove 32-bit x86 a cmdline param "no-hlt",
and the cpuinfo_x86.hlt_works_ok that it sets.

If a user wants to avoid HLT, then "idle=poll"
is much more useful, as it avoids invocation of HLT
in idle, while "no-hlt" failed to do so.

Indeed, hlt_works_ok was consulted in only 3 places.

First, in /proc/cpuinfo where "hlt_bug yes"
would be printed if and only if the user booted
the system with "no-hlt" -- as there was no other code
to set that flag.

Second, check_hlt() would not invoke halt() if "no-hlt"
were on the cmdline.

Third, it was consulted in stop_this_cpu(), which is invoked
by native_machine_halt()/reboot_interrupt()/smp_stop_nmi_callback() --
all cases where the machine is being shutdown/reset.
The flag was not consulted in the more frequently invoked
play_dead()/hlt_play_dead() used in processor offline and suspend.

Since Linux-3.0 there has been a run-time notice upon "no-hlt" invocations
indicating that it would be removed in 2012.

Signed-off-by: Len Brown <len.brown@intel.com>
Cc: x86@kernel.org

x86, 386 removal: Remove support for IRQ 13 FPU error reporting

Remove support for FPU error reporting via IRQ 13, as opposed to
exception 16 (#MF). One last remnant of i386 gone.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Alan Cox <alan@linux.intel.com>

x86: Remove the useless branch in c_start()

Since 'cpu == -1' in cpumask_next() is legal, no need to handle
'*pos == 0' specially.

About the comments:

/* just in case, cpu 0 is not the first */

A test with a cpumask in which cpu 0 is not the first has been
done, and it works well.

This patch will remove that useless branch to clean the code.

Signed-off-by: Michael Wang <wangyun@linux.vnet.ibm.com>
Cc: kjwinchester@gmail.com
Cc: borislav.petkov@amd.com
Cc: ak@linux.intel.com
Link: http://lkml.kernel.org/r/1348033343-23658-1-git-send-email-wangyun@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

x86: Simplify code by removing a !SMP #ifdefs from 'struct cpuinfo_x86'

Several fields in struct cpuinfo_x86 were not defined for the
!SMP case, likely to save space. However, those fields still
have some meaning for UP, and keeping them allows some #ifdef
removal from other files. The additional size of the UP kernel
from this change is not significant enough to worry about
keeping up the distinction:

text data bss dec hex filename
4737168 506459 972040 6215667 5ed7f3 vmlinux.o.before
4737444 506459 972040 6215943 5ed907 vmlinux.o.after

for a difference of 276 bytes for an example UP config.

If someone wants those 276 bytes back badly then it should
be implemented in a cleaner way.

Signed-off-by: Kevin Winchester <kjwinchester@gmail.com>
Cc: Steffen Persvold <sp@numascale.com>
Link: http://lkml.kernel.org/r/1324428742-12498-1-git-send-email-kjwinchester@gmail.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>

x86, microcode: Correct microcode revision format

506ed6b53e00 ("x86, intel: Output microcode revision in /proc/cpuinfo")
added microcode revision format to /proc/cpuinfo and the MCE handler in
decimal format but both AMD and Intel patch levels are handled as hex
numbers. Fix it.

Acked-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>

x86, intel: Output microcode revision in /proc/cpuinfo

I got a request to make it easier to determine the microcode
update level on Intel CPUs. This patch adds a new "microcode"
field to /proc/cpuinfo.

The microcode level is also outputed on fatal machine checks
together with the other CPUID model information.

I removed the respective code from the microcode update driver,
it just reads the field from cpu_data. Also when the microcode
is updated it fills in the new values too.

I had to add a memory barrier to native_cpuid to prevent it
being optimized away when the result is not used.

This turns out to clean up further code which already got this
information manually. This is done in followon patches.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/1318466795-7393-1-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>

x86/cpu: Clean up various files a bit

No code changes except printk levels (although some of the K6
mtrr code might be clearer if there were a few as would
splitting out some of the intel cache code).

Signed-off-by: Alan Cox <alan@linux.intel.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

x86, cpu: cpu/proc.c display cache alignment and address sizes for 32 bit

32 bits can also access x86_cache_alignment, x86_phys_bits and
x86_virt_bits, make them available to user space just as on 64 bits.

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
LKML-Reference: <1244921390.11733.30.camel@ht.satnam>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

x86: show number of core_siblings instead of thread_siblings in /proc/cpuinfo

Commit 7ad728f98162cb1af06a85b2a5fc422dddd4fb78
(cpumask: x86: convert cpu_sibling_map/cpu_core_map to cpumask_var_t)
changed the output of /proc/cpuinfo for siblings:

Example on an AMD Phenom:

physical id : 0
siblings : 1
core id : 3
cpu cores : 4

Before that commit it was:

physical id : 0
siblings : 4
core id : 3
cpu cores : 4

Instead of cpu_core_mask it now uses cpu_sibling_mask to count siblings.
This is due to the following hunk of above commit:

| --- a/arch/x86/kernel/cpu/proc.c
| +++ b/arch/x86/kernel/cpu/proc.c
| @@ -14,7 +14,7 @@ static void show_cpuinfo_core(struct seq_file *m, struct cpuinf
| if (c->x86_max_cores * smp_num_siblings > 1) {
| seq_printf(m, "physical id\t: %d\n", c->phys_proc_id);
| seq_printf(m, "siblings\t: %d\n",
| - cpus_weight(per_cpu(cpu_core_map, cpu)));
| + cpumask_weight(cpu_sibling_mask(cpu)));
| seq_printf(m, "core id\t\t: %d\n", c->cpu_core_id);
| seq_printf(m, "cpu cores\t: %d\n", c->booted_cores);
| seq_printf(m, "apicid\t\t: %d\n", c->apicid);

This was a mistake, because the impact line shows that this side-effect
was not anticipated:

Impact: reduce per-cpu size for CONFIG_CPUMASK_OFFSTACK=y

So revert the respective hunk to restore the old behavior.

[ Impact: fix sibling-info regression in /proc/cpuinfo ]

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
LKML-Reference: <20090504182859.GA29045@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

cpumask: use new cpumask functions throughout x86

Impact: cleanup

1) &cpu_online_map -> cpu_online_mask
2) first_cpu/next_cpu_nr -> cpumask_first/cpumask_next
3) cpu_*_map manipulation -> init_cpu_* / set_cpu_*

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

cpumask: x86: convert cpu_sibling_map/cpu_core_map to cpumask_var_t

Impact: reduce per-cpu size for CONFIG_CPUMASK_OFFSTACK=y

In most places it's cleaner to use the accessors cpu_sibling_mask()
and cpu_core_mask() wrappers which already exist.

I couldn't avoid cleaning up the access in oprofile, either.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

x86: remove double copy of show_cpuinfo_core for 32 and 64 bit

Impact: unification

show_cpuinfo_core is identical for 32 and 64 bit and can be unified,
and CONFIG_X86_HT inherently depends on CONFIG_X86_SMP.

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

x86/proc: fix /proc/cpuinfo cpu offline bug

Impact: fix missing CPUs in /proc/cpuinfo after CPU hotunplug/hotreplug

In my test, I found that if a cpu has been offline,
the next cpus may not be shown in the /proc/cpuinfo.

if one read() cannot consume the whole /proc/cpuinfo,
c_start() will be called again in the next read() calls.
And *pos has been increased by 1 by the caller(seq_read()).
if this time the cpu#*pos is offline, c_start() will return
NULL, and the next cpus can not be shown.

this fix use next_cpu_nr(*pos - 1, cpu_online_map) to
search the next unshown cpu.

the most easy way to reproduce this bug:
1) offline cpu#1 (cpu#0 is online)
2) dd ibs=2 if=/proc/cpuinfo
the result is that only cpu#0 is shown.
cpu#2 and cpu#3 .... cannot be shown in /proc/cpuinfo
it's bug.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

NR_CPUS: Replace NR_CPUS in arch/x86/kernel/cpu/proc.c

* Use nr_cpu_ids instead of NR_CPUS to limit traversal of cpu online map.

Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch: Remove unnecessary inclusions of asm/semaphore.h

None of these files use any of the functionality promised by
asm/semaphore.h. It's possible that they rely on it dragging in some
unrelated header file, but I can't build all these files, so we'll have
fix any build failures as they come up.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>

x86: introduce initial apicid

store initial_apicid from early identify. it is could be different from
phys_proc_id later.

also print it out in /proc/cpuinfo.

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

x86: show apicid for cpu in proc

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

x86: cosmetic unification cpu/proc|_64.c

make cpu/proc.c and cpu/proc_64.c same.

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

x86: add power management line in /proc/cpuinfo

Change /proc/cpuinfo on 32-bit, it will look like on 64-bit.
'power management' line is added and power management information
will be printed at the line.

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

x86: make cpu/proc|_64.c similar

clean up for unification.

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

x86: unify CPU feature string names

Move the CPU feature string names to a separate file (common to 32
and 64 bits); additionally, make <asm/cpufeature.h> includable by host
code in preparation for including the CPU feature strings in the boot
code.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

x86: constify function pointer tables

Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

x86: show cpuinfo only for online CPUs

Fix regressions introduced with 92cb7612aee39642d109b8d935ad265e602c0563.

It can happen that cpuinfo is displayed for CPUs that are not online or
even worse for CPUs not present at all. As an example, following was
shown for a "second" CPU of a single core K8 variant:

processor : 0
vendor_id : unknown
cpu family : 0
model : 0
model name : unknown
stepping : 0
cache size : 0 KB
fpu : yes
fpu_exception : yes
cpuid level : 0
wp : yes
flags :
bogomips : 0.00
clflush size : 0
cache_alignment : 0
address sizes : 0 bits physical, 0 bits virtual
power management:

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

x86: additional CPUID strings; fix strings for AMD-ecx

Additional CPUID strings (sse4_1, sse4_2, sse5, skinit, wdt); fix the
positioning of the AMD ecx strings (cr8_legacy was duplicated under
two different names, so the alignment of all the other strings were
off by one.)

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

x86: convert cpuinfo_x86 array to a per_cpu array

cpu_data is currently an array defined using NR_CPUS. This means that
we overallocate since we will rarely really use maximum configured cpus.
When NR_CPU count is raised to 4096 the size of cpu_data becomes
3,145,728 bytes.

These changes were adopted from the sparc64 (and ia64) code. An
additional field was added to cpuinfo_x86 to be a non-ambiguous cpu
index. This corresponds to the index into a cpumask_t as well as the
per_cpu index. It's used in various places like show_cpuinfo().

cpu_data is defined to be the boot_cpu_data structure for the NON-SMP
case.

Signed-off-by: Mike Travis <travis@sgi.com>
Acked-by: Christoph Lameter <clameter@sgi.com>
Cc: Andi Kleen <ak@suse.de>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Dmitry Torokhov <dtor@mail.ru>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: Mark M. Hoffman <mhoffman@lightlink.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

x86: Convert cpu_core_map to be a per cpu variable

This is from an earlier message from 'Christoph Lameter':

cpu_core_map is currently an array defined using NR_CPUS. This means that
we overallocate since we will rarely really use maximum configured cpu.

If we put the cpu_core_map into the per cpu area then it will be allocated
for each processor as it comes online.

This means that the core map cannot be accessed until the per cpu area
has been allocated. Xen does a weird thing here looping over all processors
and zeroing the masks that are not yet allocated and that will be zeroed
when they are allocated. I commented the code out.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

i386: move kernel/cpu

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>