From 6229ad278ca74acdbc8bd3a3d469322a3de91039 Mon Sep 17 00:00:00 2001 From: Fenghua Yu Date: Thu, 29 May 2014 11:12:30 -0700 Subject: [PATCH] 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 Link: http://lkml.kernel.org/r/1401387164-43416-3-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin --- arch/x86/include/asm/cpufeature.h | 10 ++++++++-- arch/x86/include/uapi/asm/msr-index.h | 2 ++ arch/x86/kernel/cpu/common.c | 9 +++++++++ arch/x86/kernel/cpu/scattered.c | 1 - 4 files changed, 19 insertions(+), 3 deletions(-) diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h index 2837b92..b82f951 100644 --- a/arch/x86/include/asm/cpufeature.h +++ b/arch/x86/include/asm/cpufeature.h @@ -8,7 +8,7 @@ #include #endif -#define NCAPINTS 10 /* N 32-bit words worth of info */ +#define NCAPINTS 11 /* N 32-bit words worth of info */ #define NBUGINTS 1 /* N 32-bit bug flags */ /* @@ -180,7 +180,6 @@ #define X86_FEATURE_ARAT ( 7*32+ 1) /* Always Running APIC Timer */ #define X86_FEATURE_CPB ( 7*32+ 2) /* AMD Core Performance Boost */ #define X86_FEATURE_EPB ( 7*32+ 3) /* IA32_ENERGY_PERF_BIAS support */ -#define X86_FEATURE_XSAVEOPT ( 7*32+ 4) /* Optimized Xsave */ #define X86_FEATURE_PLN ( 7*32+ 5) /* Intel Power Limit Notification */ #define X86_FEATURE_PTS ( 7*32+ 6) /* Intel Package Thermal Status */ #define X86_FEATURE_DTHERM ( 7*32+ 7) /* Digital Thermal Sensor */ @@ -226,6 +225,12 @@ #define X86_FEATURE_AVX512ER ( 9*32+27) /* AVX-512 Exponential and Reciprocal */ #define X86_FEATURE_AVX512CD ( 9*32+28) /* AVX-512 Conflict Detection */ +/* Extended state features, CPUID level 0x0000000d:1 (eax), word 10 */ +#define X86_FEATURE_XSAVEOPT (10*32+ 0) /* XSAVEOPT */ +#define X86_FEATURE_XSAVEC (10*32+ 1) /* XSAVEC */ +#define X86_FEATURE_XGETBV1 (10*32+ 2) /* XGETBV with ECX = 1 */ +#define X86_FEATURE_XSAVES (10*32+ 3) /* XSAVES/XRSTORS */ + /* * BUG word(s) */ @@ -328,6 +333,7 @@ extern const char * const x86_power_flags[32]; #define cpu_has_x2apic boot_cpu_has(X86_FEATURE_X2APIC) #define cpu_has_xsave boot_cpu_has(X86_FEATURE_XSAVE) #define cpu_has_xsaveopt boot_cpu_has(X86_FEATURE_XSAVEOPT) +#define cpu_has_xsaves boot_cpu_has(X86_FEATURE_XSAVES) #define cpu_has_osxsave boot_cpu_has(X86_FEATURE_OSXSAVE) #define cpu_has_hypervisor boot_cpu_has(X86_FEATURE_HYPERVISOR) #define cpu_has_pclmulqdq boot_cpu_has(X86_FEATURE_PCLMULQDQ) diff --git a/arch/x86/include/uapi/asm/msr-index.h b/arch/x86/include/uapi/asm/msr-index.h index fcf2b3a..5cd1569 100644 --- a/arch/x86/include/uapi/asm/msr-index.h +++ b/arch/x86/include/uapi/asm/msr-index.h @@ -297,6 +297,8 @@ #define MSR_IA32_TSC_ADJUST 0x0000003b #define MSR_IA32_BNDCFGS 0x00000d90 +#define MSR_IA32_XSS 0x00000da0 + #define FEATURE_CONTROL_LOCKED (1<<0) #define FEATURE_CONTROL_VMXON_ENABLED_INSIDE_SMX (1<<1) #define FEATURE_CONTROL_VMXON_ENABLED_OUTSIDE_SMX (1<<2) diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index a135239..e7c4b97 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -632,6 +632,15 @@ void get_cpu_cap(struct cpuinfo_x86 *c) c->x86_capability[9] = ebx; } + /* Extended state features: level 0x0000000d */ + if (c->cpuid_level >= 0x0000000d) { + u32 eax, ebx, ecx, edx; + + cpuid_count(0x0000000d, 1, &eax, &ebx, &ecx, &edx); + + c->x86_capability[10] = eax; + } + /* AMD-defined flags: level 0x80000001 */ xlvl = cpuid_eax(0x80000000); c->extended_cpuid_level = xlvl; diff --git a/arch/x86/kernel/cpu/scattered.c b/arch/x86/kernel/cpu/scattered.c index b6f794a..4a8013d 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 }, -- 2.7.4