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Sure, will update. > > On Thu, Feb 05, 2026, Nikunj A Dadhania wrote: >> Add support for AVX512 Bit Matrix Multiply (BMM) and Bit Reversal >> instructions, a feature that enables bit matrix multiply operations and >> bit reversal, which is exposed via CPUID leaf 0x80000021_EAX[23]. >> >> Expose the support to guests when available by including it in the CPUID > > Advertise to userspace. The VMM decides whether or not to enumerate features to > guests. Ack. Regards Nikunj > >> leaf 0x80000021_EAX feature list. >> >> While at it, reorder PREFETCHI to match the bit position order in CPUID >> leaf 0x80000021_EAX for better organization. >> >> Signed-off-by: Nikunj A Dadhania >> --- >> >> AMD64 Bit Matrix Multiply and Bit Reversal Instructions >> Publication #69192 Revision: 1.00 >> Issue Date: January 2026 >> >> https://docs.amd.com/v/u/en-US/69192-PUB >> --- >> arch/x86/include/asm/cpufeatures.h | 1 + >> arch/x86/kvm/cpuid.c | 3 ++- >> 2 files changed, 3 insertions(+), 1 deletion(-) >> >> diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h >> index c3b53beb1300..2f1583c4bdc0 100644 >> --- a/arch/x86/include/asm/cpufeatures.h >> +++ b/arch/x86/include/asm/cpufeatures.h >> @@ -472,6 +472,7 @@ >> #define X86_FEATURE_GP_ON_USER_CPUID (20*32+17) /* User CPUID faulting */ >> >> #define X86_FEATURE_PREFETCHI (20*32+20) /* Prefetch Data/Instruction to Cache Level */ >> +#define X86_FEATURE_AVX512_BMM (20*32+23) /* AVX512 Bit Matrix Multiply instructions */ >> #define X86_FEATURE_SBPB (20*32+27) /* Selective Branch Prediction Barrier */ >> #define X86_FEATURE_IBPB_BRTYPE (20*32+28) /* MSR_PRED_CMD[IBPB] flushes all branch type predictions */ >> #define X86_FEATURE_SRSO_NO (20*32+29) /* CPU is not affected by SRSO */ >> diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c >> index 88a5426674a1..b36e8f10f509 100644 >> --- a/arch/x86/kvm/cpuid.c >> +++ b/arch/x86/kvm/cpuid.c >> @@ -1218,11 +1218,12 @@ void kvm_set_cpu_caps(void) >> F(NULL_SEL_CLR_BASE), >> /* UpperAddressIgnore */ >> F(AUTOIBRS), >> - F(PREFETCHI), >> EMULATED_F(NO_SMM_CTL_MSR), >> /* PrefetchCtlMsr */ >> /* GpOnUserCpuid */ >> /* EPSF */ >> + F(PREFETCHI), >> + F(AVX512_BMM), >> SYNTHESIZED_F(SBPB), >> SYNTHESIZED_F(IBPB_BRTYPE), >> SYNTHESIZED_F(SRSO_NO), >> >> base-commit: e89f0e9a0a007e8c3afb8ecd739c0b3255422b00 >> -- >> 2.48.1 >>