diff options
author | Fenghua Yu <fenghua.yu@intel.com> | 2014-05-29 11:12:30 -0700 |
---|---|---|
committer | H. Peter Anvin <hpa@linux.intel.com> | 2014-05-29 14:24:28 -0700 |
commit | 6229ad278ca74acdbc8bd3a3d469322a3de91039 (patch) | |
tree | d6e72f6129630ddbf3d46b9902fecf0fb331f364 /arch/x86/kernel/cpu/scattered.c | |
parent | 446fd806f5408b623fa51f3aa084e56844563779 (diff) |
x86/xsaves: Detect xsaves/xrstors feature
Detect the xsaveopt, xsavec, xgetbv, and xsaves features in processor extended
state enumberation sub-leaf (eax=0x0d, ecx=1):
Bit 00: XSAVEOPT is available
Bit 01: Supports XSAVEC and the compacted form of XRSTOR if set
Bit 02: Supports XGETBV with ECX = 1 if set
Bit 03: Supports XSAVES/XRSTORS and IA32_XSS if set
The above features are defined in the new word 10 in cpu features.
The IA32_XSS MSR (index DA0H) contains a state-component bitmap that specifies
the state components that software has enabled xsaves and xrstors to manage.
If the bit corresponding to a state component is clear in XCR0 | IA32_XSS,
xsaves and xrstors will not operate on that state component, regardless of
the value of the instruction mask.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Link: http://lkml.kernel.org/r/1401387164-43416-3-git-send-email-fenghua.yu@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'arch/x86/kernel/cpu/scattered.c')
-rw-r--r-- | arch/x86/kernel/cpu/scattered.c | 1 |
1 files changed, 0 insertions, 1 deletions
diff --git a/arch/x86/kernel/cpu/scattered.c b/arch/x86/kernel/cpu/scattered.c index b6f794aa1693..4a8013d55947 100644 --- a/arch/x86/kernel/cpu/scattered.c +++ b/arch/x86/kernel/cpu/scattered.c @@ -38,7 +38,6 @@ void init_scattered_cpuid_features(struct cpuinfo_x86 *c) { X86_FEATURE_PTS, CR_EAX, 6, 0x00000006, 0 }, { X86_FEATURE_APERFMPERF, CR_ECX, 0, 0x00000006, 0 }, { X86_FEATURE_EPB, CR_ECX, 3, 0x00000006, 0 }, - { X86_FEATURE_XSAVEOPT, CR_EAX, 0, 0x0000000d, 1 }, { X86_FEATURE_HW_PSTATE, CR_EDX, 7, 0x80000007, 0 }, { X86_FEATURE_CPB, CR_EDX, 9, 0x80000007, 0 }, { X86_FEATURE_PROC_FEEDBACK, CR_EDX,11, 0x80000007, 0 }, |