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x86, fpu: Extend the use of static_cpu_has_safe
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It may be necessary to save and restore the FPU context during EFI runtime
system services calls. However, this may happen during boot and before
alternatives have run. Thus, we need to use static_cpu_has_safe instead.

The rationale behind the use of static_cpu_has_safe is the same as in
commit 5f8c421 ("x86, fpu: Use static_cpu_has_safe
before alternatives") by Borislav Petkov.

Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Cc: Borislav Petkov <bp@suse.de>
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Matt Fleming committed Apr 17, 2014
1 parent 62fa6e6 commit c6b4069
Showing 1 changed file with 5 additions and 5 deletions.
10 changes: 5 additions & 5 deletions arch/x86/include/asm/fpu-internal.h
Original file line number Diff line number Diff line change
Expand Up @@ -87,22 +87,22 @@ static inline int is_x32_frame(void)

static __always_inline __pure bool use_eager_fpu(void)
{
return static_cpu_has(X86_FEATURE_EAGER_FPU);
return static_cpu_has_safe(X86_FEATURE_EAGER_FPU);
}

static __always_inline __pure bool use_xsaveopt(void)
{
return static_cpu_has(X86_FEATURE_XSAVEOPT);
return static_cpu_has_safe(X86_FEATURE_XSAVEOPT);
}

static __always_inline __pure bool use_xsave(void)
{
return static_cpu_has(X86_FEATURE_XSAVE);
return static_cpu_has_safe(X86_FEATURE_XSAVE);
}

static __always_inline __pure bool use_fxsr(void)
{
return static_cpu_has(X86_FEATURE_FXSR);
return static_cpu_has_safe(X86_FEATURE_FXSR);
}

static inline void fx_finit(struct i387_fxsave_struct *fx)
Expand Down Expand Up @@ -293,7 +293,7 @@ static inline int restore_fpu_checking(struct task_struct *tsk)
/* AMD K7/K8 CPUs don't save/restore FDP/FIP/FOP unless an exception
is pending. Clear the x87 state here by setting it to fixed
values. "m" is a random variable that should be in L1 */
if (unlikely(static_cpu_has(X86_FEATURE_FXSAVE_LEAK))) {
if (unlikely(static_cpu_has_safe(X86_FEATURE_FXSAVE_LEAK))) {
asm volatile(
"fnclex\n\t"
"emms\n\t"
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