Commit fb3146b4 authored Mar 10, 2023 by Sean Christopherson

KVM: x86: Add a helper to query whether or not a vCPU has ever run



Add a helper to query if a vCPU has run so that KVM doesn't have to open
code the check on last_vmentry_cpu being set to a magic value.

No functional change intended.

Suggested-by: Xiaoyao Li <xiaoyao.li@intel.com>
Cc: Like Xu <like.xu.linux@gmail.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Link: https://lore.kernel.org/r/20230311004618.920745-3-seanjc@google.com


Signed-off-by: Sean Christopherson <seanjc@google.com>

parent b1932c5c

arch/x86/kvm/cpuid.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -420,7 +420,7 @@ static int kvm_set_cpuid(struct kvm_vcpu vcpu, struct kvm_cpuid_entry2 e2,
		* KVM_SET_CPUID{,2} again. To support this legacy behavior, check
		* whether the supplied CPUID data is equal to what's already set.
		*/
		if (vcpu->arch.last_vmentry_cpu != -1) {
		if (kvm_vcpu_has_run(vcpu)) {
		r = kvm_cpuid_check_equal(vcpu, e2, nent);
		if (r)
		return r;

arch/x86/kvm/mmu/mmu.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -5393,7 +5393,7 @@ void kvm_mmu_after_set_cpuid(struct kvm_vcpu *vcpu)
		* Changing guest CPUID after KVM_RUN is forbidden, see the comment in
		* kvm_arch_vcpu_ioctl().
		*/
		KVM_BUG_ON(vcpu->arch.last_vmentry_cpu != -1, vcpu->kvm);
		KVM_BUG_ON(kvm_vcpu_has_run(vcpu), vcpu->kvm);
		}

		void kvm_mmu_reset_context(struct kvm_vcpu *vcpu)

arch/x86/kvm/x86.h

+5 −0

Original line number	Diff line number	Diff line
		@@ -83,6 +83,11 @@ static inline unsigned int __shrink_ple_window(unsigned int val,
		void kvm_service_local_tlb_flush_requests(struct kvm_vcpu *vcpu);
		int kvm_check_nested_events(struct kvm_vcpu *vcpu);

		static inline bool kvm_vcpu_has_run(struct kvm_vcpu *vcpu)
		{
		return vcpu->arch.last_vmentry_cpu != -1;
		}

		static inline bool kvm_is_exception_pending(struct kvm_vcpu *vcpu)
		{
		return vcpu->arch.exception.pending \|\|