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Message-Id: <20221125125845.1182922-9-jiaxi.chen@linux.intel.com> Date: Fri, 25 Nov 2022 20:58:45 +0800 From: Jiaxi Chen <jiaxi.chen@...ux.intel.com> To: kvm@...r.kernel.org Cc: tglx@...utronix.de, mingo@...hat.com, bp@...en8.de, dave.hansen@...ux.intel.com, x86@...nel.org, hpa@...or.com, seanjc@...gle.com, pbonzini@...hat.com, ndesaulniers@...gle.com, alexandre.belloni@...tlin.com, peterz@...radead.org, jpoimboe@...nel.org, chang.seok.bae@...el.com, pawan.kumar.gupta@...ux.intel.com, babu.moger@....com, jmattson@...gle.com, sandipan.das@....com, tony.luck@...el.com, sathyanarayanan.kuppuswamy@...ux.intel.com, fenghua.yu@...el.com, keescook@...omium.org, nathan@...nel.org, linux-kernel@...r.kernel.org Subject: [PATCH v5 8/8] KVM: x86: Advertise PREFETCHIT0/1 CPUID to user space Latest Intel platform Granite Rapids has introduced a new instruction - PREFETCHIT0/1, which moves code to memory (cache) closer to the processor depending on specific hints. The bit definition: CPUID.(EAX=7,ECX=1):EDX[bit 14] PREFETCHIT0/1 is on a KVM-only subleaf. Plus an x86_FEATURE definition for this feature bit to direct it to the KVM entry. Advertise PREFETCHIT0/1 to KVM userspace. This is safe because there are no new VMX controls or additional host enabling required for guests to use this feature. Signed-off-by: Jiaxi Chen <jiaxi.chen@...ux.intel.com> --- arch/x86/kvm/cpuid.c | 2 +- arch/x86/kvm/reverse_cpuid.h | 1 + 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index c4ea8f593b72..f60e9fa1b777 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -668,7 +668,7 @@ void kvm_set_cpu_caps(void) ); kvm_cpu_cap_init_kvm_defined(CPUID_7_1_EDX, - F(AVX_VNNI_INT8) | F(AVX_NE_CONVERT) + F(AVX_VNNI_INT8) | F(AVX_NE_CONVERT) | F(PREFETCHITI) ); kvm_cpu_cap_mask(CPUID_D_1_EAX, diff --git a/arch/x86/kvm/reverse_cpuid.h b/arch/x86/kvm/reverse_cpuid.h index 43eff7207e01..203fdad07bae 100644 --- a/arch/x86/kvm/reverse_cpuid.h +++ b/arch/x86/kvm/reverse_cpuid.h @@ -40,6 +40,7 @@ enum kvm_only_cpuid_leafs { /* Intel-defined sub-features, CPUID level 0x00000007:1 (EDX) */ #define X86_FEATURE_AVX_VNNI_INT8 KVM_X86_FEATURE(CPUID_7_1_EDX, 4) #define X86_FEATURE_AVX_NE_CONVERT KVM_X86_FEATURE(CPUID_7_1_EDX, 5) +#define X86_FEATURE_PREFETCHITI KVM_X86_FEATURE(CPUID_7_1_EDX, 14) struct cpuid_reg { u32 function; -- 2.27.0
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