linux-stable.git/arch/x86/kernel/cpu/cyrix.c, branch linux-4.9.y

x86/CPU: Use correct macros for Cyrix calls

2019-11-25T08:52:46+00:00

[ Upstream commit 03b099bdcdf7125d4a63dc9ddeefdd454e05123d ]

There are comments in processor-cyrix.h advising you to _not_ make calls
using the deprecated macros in this style:

  setCx86_old(CX86_CCR4, getCx86_old(CX86_CCR4) | 0x80);

This is because it expands the macro into a non-functioning calling
sequence. The calling order must be:

  outb(CX86_CCR2, 0x22);
  inb(0x23);

From the comments:

 * When using the old macros a line like
 *   setCx86(CX86_CCR2, getCx86(CX86_CCR2) | 0x88);
 * gets expanded to:
 *  do {
 *    outb((CX86_CCR2), 0x22);
 *    outb((({
 *        outb((CX86_CCR2), 0x22);
 *        inb(0x23);
 *    }) | 0x88), 0x23);
 *  } while (0);

The new macros fix this problem, so use them instead.

Signed-off-by: Matthew Whitehead 
Signed-off-by: Borislav Petkov 
Reviewed-by: Andy Lutomirski 
Cc: Greg Kroah-Hartman 
Cc: "H. Peter Anvin" 
Cc: Ingo Molnar 
Cc: Jia Zhang 
Cc: Peter Zijlstra 
Cc: Philippe Ombredanne 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/20180921212041.13096-2-tedheadster@gmail.com
Signed-off-by: Sasha Levin

x86/cpu/cyrix: Use correct macros for Cyrix calls on Geode processors

2019-04-20T07:07:50+00:00

[ Upstream commit 18fb053f9b827bd98cfc64f2a35df8ab19745a1d ]

There are comments in processor-cyrix.h advising you to _not_ make calls
using the deprecated macros in this style:

  setCx86_old(CX86_CCR4, getCx86_old(CX86_CCR4) | 0x80);

This is because it expands the macro into a non-functioning calling
sequence. The calling order must be:

  outb(CX86_CCR2, 0x22);
  inb(0x23);

From the comments:

 * When using the old macros a line like
 *   setCx86(CX86_CCR2, getCx86(CX86_CCR2) | 0x88);
 * gets expanded to:
 *  do {
 *    outb((CX86_CCR2), 0x22);
 *    outb((({
 *        outb((CX86_CCR2), 0x22);
 *        inb(0x23);
 *    }) | 0x88), 0x23);
 *  } while (0);

The new macros fix this problem, so use them instead. Tested on an
actual Geode processor.

Signed-off-by: Matthew Whitehead 
Signed-off-by: Thomas Gleixner 
Cc: luto@kernel.org
Link: https://lkml.kernel.org/r/1552596361-8967-2-git-send-email-tedheadster@gmail.com
Signed-off-by: Sasha Levin

x86/cpu/cyrix: Add alternative Device ID of Geode GX1 SoC

2018-11-10T15:42:48+00:00

[ Upstream commit ae1d557d8f30cb097b4d1f2ab04fa294588ee1cf ]

A SoC variant of Geode GX1, notably NSC branded SC1100, seems to
report an inverted Device ID in its DIR0 configuration register,
specifically 0xb instead of the expected 0x4.

Catch this presumably quirky version so it's properly recognized
as GX1 and has its cache switched to write-back mode, which provides
a significant performance boost in most workloads.

SC1100's datasheet "Geode™ SC1100 Information Appliance On a Chip",
states in section 1.1.7.1 "Device ID" that device identification
values are specified in SC1100's device errata. These, however,
seem to not have been publicly released.

Wading through a number of boot logs and /proc/cpuinfo dumps found on
pastebin and blogs, this patch should mostly be relevant for a number
of now admittedly aging Soekris NET4801 and PC Engines WRAP devices,
the latter being the platform this issue was discovered on.
Performance impact was verified using "openssl speed", with
write-back caching scaling throughput between -3% and +41%.

Signed-off-by: Christian Sünkenberg 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/1496596719.26725.14.camel@student.kit.edu
Signed-off-by: Ingo Molnar 
Signed-off-by: Sasha Levin

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

2018-02-22T14:43:55+00:00

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 
[ Updated it to more recent kernels. ]
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
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 
Signed-off-by: Greg Kroah-Hartman

x86/cpufeature: Replace cpu_has_fpu with boot_cpu_has() usage

2016-04-13T09:37:40+00:00

Use static_cpu_has() in the timing-sensitive paths in fpstate_init() and
fpu__copy().

While at it, simplify the use in init_cyrix() and get rid of the ternary
operator.

Signed-off-by: Borislav Petkov 
Cc: Andy Lutomirski 
Cc: Borislav Petkov 
Cc: Brian Gerst 
Cc: Denys Vlasenko 
Cc: H. Peter Anvin 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/1459801503-15600-6-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar

Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2016-03-15T16:32:27+00:00

Pull x86 asm updates from Ingo Molnar:
 "This is another big update. Main changes are:

   - lots of x86 system call (and other traps/exceptions) entry code
     enhancements.  In particular the complex parts of the 64-bit entry
     code have been migrated to C code as well, and a number of dusty
     corners have been refreshed.  (Andy Lutomirski)

   - vDSO special mapping robustification and general cleanups (Andy
     Lutomirski)

   - cpufeature refactoring, cleanups and speedups (Borislav Petkov)

   - lots of other changes ..."

* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (64 commits)
  x86/cpufeature: Enable new AVX-512 features
  x86/entry/traps: Show unhandled signal for i386 in do_trap()
  x86/entry: Call enter_from_user_mode() with IRQs off
  x86/entry/32: Change INT80 to be an interrupt gate
  x86/entry: Improve system call entry comments
  x86/entry: Remove TIF_SINGLESTEP entry work
  x86/entry/32: Add and check a stack canary for the SYSENTER stack
  x86/entry/32: Simplify and fix up the SYSENTER stack #DB/NMI fixup
  x86/entry: Only allocate space for tss_struct::SYSENTER_stack if needed
  x86/entry: Vastly simplify SYSENTER TF (single-step) handling
  x86/entry/traps: Clear DR6 early in do_debug() and improve the comment
  x86/entry/traps: Clear TIF_BLOCKSTEP on all debug exceptions
  x86/entry/32: Restore FLAGS on SYSEXIT
  x86/entry/32: Filter NT and speed up AC filtering in SYSENTER
  x86/entry/compat: In SYSENTER, sink AC clearing below the existing FLAGS test
  selftests/x86: In syscall_nt, test NT|TF as well
  x86/asm-offsets: Remove PARAVIRT_enabled
  x86/entry/32: Introduce and use X86_BUG_ESPFIX instead of paravirt_enabled
  uprobes: __create_xol_area() must nullify xol_mapping.fault
  x86/cpufeature: Create a new synthetic cpu capability for machine check recovery
  ...

x86/cpu: Convert printk(KERN_ ...) to pr_(...)

2016-02-03T09:30:03+00:00

 - Use the more current logging style pr_(...) instead of the old
   printk(KERN_ ...).

 - Convert pr_warning() to pr_warn().

Signed-off-by: Chen Yucong 
Cc: Borislav Petkov 
Cc: H. Peter Anvin 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/1454384702-21707-1-git-send-email-slaoub@gmail.com
Signed-off-by: Ingo Molnar

x86/cpufeature: Carve out X86_FEATURE_*

2016-01-30T10:22:17+00:00

Move them to a separate header and have the following
dependency:

  x86/cpufeatures.h <- x86/processor.h <- x86/cpufeature.h

This makes it easier to use the header in asm code and not
include the whole cpufeature.h and add guards for asm.

Suggested-by: H. Peter Anvin 
Signed-off-by: Borislav Petkov 
Cc: Andy Lutomirski 
Cc: Borislav Petkov 
Cc: Brian Gerst 
Cc: Denys Vlasenko 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/1453842730-28463-5-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar

x86: Delete non-required instances of include

2014-01-07T05:25:18+00:00

None of these files are actually using any __init type directives
and hence don't need to include .  Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.

[ hpa: undid incorrect removal from arch/x86/kernel/head_32.S ]

Signed-off-by: Paul Gortmaker 
Link: http://lkml.kernel.org/r/1389054026-12947-1-git-send-email-paul.gortmaker@windriver.com
Signed-off-by: H. Peter Anvin

x86: delete __cpuinit usage from all x86 files

2013-07-14T23:36:56+00:00

The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications.  For example, the fix in
commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.

After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out.  Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.

Note that some harmless section mismatch warnings may result, since
notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c)
are flagged as __cpuinit  -- so if we remove the __cpuinit from
arch specific callers, we will also get section mismatch warnings.
As an intermediate step, we intend to turn the linux/init.h cpuinit
content into no-ops as early as possible, since that will get rid
of these warnings.  In any case, they are temporary and harmless.

This removes all the arch/x86 uses of the __cpuinit macros from
all C files.  x86 only had the one __CPUINIT used in assembly files,
and it wasn't paired off with a .previous or a __FINIT, so we can
delete it directly w/o any corresponding additional change there.

[1] https://lkml.org/lkml/2013/5/20/589

Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: "H. Peter Anvin" 
Cc: x86@kernel.org
Acked-by: Ingo Molnar 
Acked-by: Thomas Gleixner 
Acked-by: H. Peter Anvin 
Signed-off-by: Paul Gortmaker