linux-stable.git/arch/x86/kernel/cpu/proc.c, branch linux-3.16.y Linux kernel stable tree x86/cpu: Rename cpu_data.x86_mask to cpu_data.x86_stepping 2020-06-11T18:05:55+00:00 Jia Zhang qianyue.zj@alibaba-inc.com 2018-01-01T01:52:10+00:00 582f3009d4511bdd12a4d88ae52da46359cd88aa commit b399151cb48db30ad1e0e93dd40d68c6d007b637 upstream. 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [bwh: Backported to 3.16: - Drop changes in arch/x86/lib/cpu.c - Adjust filenames, context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit b399151cb48db30ad1e0e93dd40d68c6d007b637 upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.16:
 - Drop changes in arch/x86/lib/cpu.c
 - Adjust filenames, context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
x86/cpufeature: Add bug flags to /proc/cpuinfo 2019-05-22T22:15:00+00:00 Borislav Petkov bp@suse.de 2014-06-24T11:25:03+00:00 dc2feeef2101fcb06a82951f7cd6ac8cd28bec58 commit 80a208bd3948aceddf0429bd9f9b4cd858d526df upstream. 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> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 80a208bd3948aceddf0429bd9f9b4cd858d526df upstream.

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>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
x86/cpu: Change type of x86_cache_size variable to unsigned int 2018-03-19T18:59:10+00:00 Gustavo A. R. Silva garsilva@embeddedor.com 2018-02-13T19:22:08+00:00 98fbe878ffa97973502c1a75b0b2130ae9091b97 commit 24dbc6000f4b9b0ef5a9daecb161f1907733765a upstream. 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> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 24dbc6000f4b9b0ef5a9daecb161f1907733765a upstream.

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>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
x86/cpu: Always print SMP information in /proc/cpuinfo 2013-11-06T07:13:56+00:00 HATAYAMA Daisuke d.hatayama@jp.fujitsu.com 2013-11-04T17:15:48+00:00 a477c8594bee3bff639739c48258a8c737ab721e 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> 
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 2013-06-06T21:32:04+00:00 H. Peter Anvin hpa@zytor.com 2013-04-29T14:04:20+00:00 60e019eb37a8d989031ad47ae9810453536f3127 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> 
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 2013-04-02T17:12:54+00:00 Borislav Petkov bp@suse.de 2013-03-20T14:07:26+00:00 c5b41a67505cc3c9744d8f105c63a3bf3c443a01 ... 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> 
... 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 2013-04-02T17:12:53+00:00 Borislav Petkov bp@suse.de 2013-03-20T14:07:25+00:00 93a829e8e2c292f1d30155f64803101ca1cb7d3d ... 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> 
... 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 2013-04-02T17:12:52+00:00 Borislav Petkov bp@suse.de 2013-03-20T14:07:24+00:00 e2604b49e8a8827e8bc5b61bc0c5a889e028fdad ... 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> 
... 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 2013-02-10T08:32:22+00:00 Len Brown len.brown@intel.com 2013-02-10T07:28:46+00:00 27be457000211a6903968dfce06d5f73f051a217 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 
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 2012-12-17T19:42:40+00:00 H. Peter Anvin hpa@linux.intel.com 2012-12-17T19:26:31+00:00 bc3eba60682750dd7b45ea616d65c926fc3b8be8 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> 
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>