From: Isaku Yamahata <isaku.yamahata@xxxxxxxxx> The x86 backend should check the consistency of KVM_SET_CPUID2 because it has its constraint. Add a callback for it. The backend code will come as another patch. Suggested-by: Sean Christopherson <seanjc@xxxxxxxxxx> Link: https://lore.kernel.org/lkml/ZDiGpCkXOcCm074O@xxxxxxxxxx/ Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx> --- arch/x86/include/asm/kvm-x86-ops.h | 2 ++ arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kvm/cpuid.c | 20 ++++++++++++-------- 3 files changed, 15 insertions(+), 8 deletions(-) diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h index ee0b82817c63..527db174d6b5 100644 --- a/arch/x86/include/asm/kvm-x86-ops.h +++ b/arch/x86/include/asm/kvm-x86-ops.h @@ -20,6 +20,8 @@ KVM_X86_OP(hardware_disable) KVM_X86_OP(hardware_unsetup) KVM_X86_OP_OPTIONAL_RET0(offline_cpu) KVM_X86_OP(has_emulated_msr) +/* TODO: Once all backend implemented this op, remove _OPTIONAL_RET0. */ +KVM_X86_OP_OPTIONAL_RET0(vcpu_check_cpuid) KVM_X86_OP(vcpu_after_set_cpuid) KVM_X86_OP(is_vm_type_supported) KVM_X86_OP_OPTIONAL(max_vcpus); diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 54ac65b75f18..b83a790b01c8 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1655,6 +1655,7 @@ struct kvm_x86_ops { void (*hardware_unsetup)(void); int (*offline_cpu)(void); bool (*has_emulated_msr)(struct kvm *kvm, u32 index); + int (*vcpu_check_cpuid)(struct kvm_vcpu *vcpu, struct kvm_cpuid_entry2 *e2, int nent); void (*vcpu_after_set_cpuid)(struct kvm_vcpu *vcpu); bool (*is_vm_type_supported)(unsigned long vm_type); diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 8cdcd6f406aa..b57006943247 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -136,6 +136,7 @@ static int kvm_check_cpuid(struct kvm_vcpu *vcpu, { struct kvm_cpuid_entry2 *best; u64 xfeatures; + int r; /* * The existing code assumes virtual address is 48-bit or 57-bit in the @@ -155,15 +156,18 @@ static int kvm_check_cpuid(struct kvm_vcpu *vcpu, * enabling in the FPU, e.g. to expand the guest XSAVE state size. */ best = cpuid_entry2_find(entries, nent, 0xd, 0); - if (!best) - return 0; - - xfeatures = best->eax | ((u64)best->edx << 32); - xfeatures &= XFEATURE_MASK_USER_DYNAMIC; - if (!xfeatures) - return 0; + if (best) { + xfeatures = best->eax | ((u64)best->edx << 32); + xfeatures &= XFEATURE_MASK_USER_DYNAMIC; + if (xfeatures) { + r = fpu_enable_guest_xfd_features(&vcpu->arch.guest_fpu, + xfeatures); + if (r) + return r; + } + } - return fpu_enable_guest_xfd_features(&vcpu->arch.guest_fpu, xfeatures); + return static_call(kvm_x86_vcpu_check_cpuid)(vcpu, entries, nent); } /* Check whether the supplied CPUID data is equal to what is already set for the vCPU. */ -- 2.25.1
