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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2016-03-12 20:09:25 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-03-12 20:09:25 -0800 |
| commit | 2f51c8204ab3ea211ac92f3b7b88a38595ed6412 (patch) | |
| tree | b872e12090ea271ea951f2446e840dc4d0f52e43 /arch/x86/kernel/fpu/init.c | |
| parent | fda604a4daa19ead458ce5471892fa1d4b382d82 (diff) | |
| parent | 452308de61056a539352a9306c46716d7af8a1f1 (diff) | |
Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
"This fixes 3 FPU handling related bugs, an EFI boot crash and a
runtime warning.
The EFI fix arrived late but I didn't want to delay it to after v4.5
because the effects are pretty bad for the systems that are affected
by it"
[ Actually, I don't think the EFI fix really matters yet, because we
haven't switched to the separate EFI page tables in mainline yet ]
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/efi: Fix boot crash by always mapping boot service regions into new EFI page tables
x86/fpu: Fix eager-FPU handling on legacy FPU machines
x86/delay: Avoid preemptible context checks in delay_mwaitx()
x86/fpu: Revert ("x86/fpu: Disable AVX when eagerfpu is off")
x86/fpu: Fix 'no387' regression
Diffstat (limited to 'arch/x86/kernel/fpu/init.c')
| -rw-r--r-- | arch/x86/kernel/fpu/init.c | 22 |
1 files changed, 9 insertions, 13 deletions
diff --git a/arch/x86/kernel/fpu/init.c b/arch/x86/kernel/fpu/init.c index 6d9f0a7ef4c8..bd08fb77073d 100644 --- a/arch/x86/kernel/fpu/init.c +++ b/arch/x86/kernel/fpu/init.c @@ -78,13 +78,15 @@ static void fpu__init_system_early_generic(struct cpuinfo_x86 *c) cr0 &= ~(X86_CR0_TS | X86_CR0_EM); write_cr0(cr0); - asm volatile("fninit ; fnstsw %0 ; fnstcw %1" - : "+m" (fsw), "+m" (fcw)); + if (!test_bit(X86_FEATURE_FPU, (unsigned long *)cpu_caps_cleared)) { + asm volatile("fninit ; fnstsw %0 ; fnstcw %1" + : "+m" (fsw), "+m" (fcw)); - if (fsw == 0 && (fcw & 0x103f) == 0x003f) - set_cpu_cap(c, X86_FEATURE_FPU); - else - clear_cpu_cap(c, X86_FEATURE_FPU); + if (fsw == 0 && (fcw & 0x103f) == 0x003f) + set_cpu_cap(c, X86_FEATURE_FPU); + else + clear_cpu_cap(c, X86_FEATURE_FPU); + } #ifndef CONFIG_MATH_EMULATION if (!cpu_has_fpu) { @@ -132,7 +134,7 @@ static void __init fpu__init_system_generic(void) * Set up the legacy init FPU context. (xstate init might overwrite this * with a more modern format, if the CPU supports it.) */ - fpstate_init_fxstate(&init_fpstate.fxsave); + fpstate_init(&init_fpstate); fpu__init_system_mxcsr(); } @@ -300,12 +302,6 @@ u64 __init fpu__get_supported_xfeatures_mask(void) static void __init fpu__clear_eager_fpu_features(void) { setup_clear_cpu_cap(X86_FEATURE_MPX); - setup_clear_cpu_cap(X86_FEATURE_AVX); - setup_clear_cpu_cap(X86_FEATURE_AVX2); - setup_clear_cpu_cap(X86_FEATURE_AVX512F); - setup_clear_cpu_cap(X86_FEATURE_AVX512PF); - setup_clear_cpu_cap(X86_FEATURE_AVX512ER); - setup_clear_cpu_cap(X86_FEATURE_AVX512CD); } /* |