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Bae" , linux-kernel@vger.kernel.org Cc: kvm@vger.kernel.org, pbonzini@redhat.com, seanjc@google.com, Zhao Liu , Binbin Wu References: <20260708210118.402005-1-chang.seok.bae@intel.com> Content-Language: en-US From: Xiaoyao Li In-Reply-To: <20260708210118.402005-1-chang.seok.bae@intel.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 7/9/2026 5:01 AM, Chang S. Bae wrote: > AMX-TF32 enumeration was added based on the Intel documentation [1]. The > recent update removed the feature, indicating that the feature is no > longer planned for hardware implementation. Patch looks good to me. BTW, I think the bit cannot be assigned for new other usage in the future and becomes reserved forever, right? > [1] Intel Architecture Instruction Set Extensions and Future Features > > Cc: Zhao Liu > Cc: Binbin Wu > Signed-off-by: Chang S. Bae > --- > Note: The feature first appeared in the September 2025 revision of the > document and was removed in the June 2026 revision. > --- > arch/x86/kvm/cpuid.c | 1 - > arch/x86/kvm/reverse_cpuid.h | 1 - > 2 files changed, 2 deletions(-) > > diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c > index 591d2294acd7..759a1c557080 100644 > --- a/arch/x86/kvm/cpuid.c > +++ b/arch/x86/kvm/cpuid.c > @@ -1082,7 +1082,6 @@ void kvm_initialize_cpu_caps(void) > F(AMX_COMPLEX_ALIAS), > F(AMX_FP16_ALIAS), > F(AMX_FP8), > - F(AMX_TF32), > F(AMX_AVX512), > F(AMX_MOVRS), > ); > diff --git a/arch/x86/kvm/reverse_cpuid.h b/arch/x86/kvm/reverse_cpuid.h > index 2ad25781cefb..1bb13903c5b2 100644 > --- a/arch/x86/kvm/reverse_cpuid.h > +++ b/arch/x86/kvm/reverse_cpuid.h > @@ -56,7 +56,6 @@ > #define X86_FEATURE_AMX_COMPLEX_ALIAS KVM_X86_FEATURE(CPUID_1E_1_EAX, 2) > #define X86_FEATURE_AMX_FP16_ALIAS KVM_X86_FEATURE(CPUID_1E_1_EAX, 3) > #define X86_FEATURE_AMX_FP8 KVM_X86_FEATURE(CPUID_1E_1_EAX, 4) > -#define X86_FEATURE_AMX_TF32 KVM_X86_FEATURE(CPUID_1E_1_EAX, 6) > #define X86_FEATURE_AMX_AVX512 KVM_X86_FEATURE(CPUID_1E_1_EAX, 7) > #define X86_FEATURE_AMX_MOVRS KVM_X86_FEATURE(CPUID_1E_1_EAX, 8) >