AVX-IFMA is a new instruction in the latest Intel platform Sierra Forest. AVX-IFMA packed multiplies unsigned 52-bit integers and add the low/high 52-bit products to Qword Accumulators. The bit definition: CPUID.(EAX=7,ECX=1):EAX[bit 23] This patch enables this CPUID in the kernel feature bits and expose it to guest OS. Signed-off-by: Jiaxi Chen <jiaxi.chen@xxxxxxxxxxxxxxx> --- arch/x86/include/asm/cpufeatures.h | 1 + arch/x86/kvm/cpuid.c | 4 ++-- 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h index 9313240e3cdd..a682f646243f 100644 --- a/arch/x86/include/asm/cpufeatures.h +++ b/arch/x86/include/asm/cpufeatures.h @@ -310,6 +310,7 @@ #define X86_FEATURE_AVX512_BF16 (12*32+ 5) /* AVX512 BFLOAT16 instructions */ #define X86_FEATURE_CMPCCXADD (12*32+ 7) /* CMPccXADD instructions */ #define X86_FEATURE_AMX_FP16 (12*32+21) /* AMX fp16 Support */ +#define X86_FEATURE_AVX_IFMA (12*32+23) /* Support for VPMADD52[H,L]UQ */ /* AMD-defined CPU features, CPUID level 0x80000008 (EBX), word 13 */ #define X86_FEATURE_CLZERO (13*32+ 0) /* CLZERO instruction */ diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index d983ddb974ba..837bcd1373e5 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -657,8 +657,8 @@ void kvm_set_cpu_caps(void) kvm_cpu_cap_set(X86_FEATURE_SPEC_CTRL_SSBD); kvm_cpu_cap_mask(CPUID_7_1_EAX, - F(AVX_VNNI) | F(AVX512_BF16) | F(CMPCCXADD) | F(AMX_FP16) - ); + F(AVX_VNNI) | F(AVX512_BF16) | F(CMPCCXADD) | F(AMX_FP16) | + F(AVX_IFMA)); kvm_cpu_cap_mask(CPUID_D_1_EAX, F(XSAVEOPT) | F(XSAVEC) | F(XGETBV1) | F(XSAVES) | f_xfd -- 2.27.0
