KVM: MMU: do not mark accessed bit on pte write path (d01f8d5e) · Commits · 戴 / test

arch/x86/include/asm/kvm_host.h

+0 −1

Original line number	Diff line number	Diff line
		@@ -356,7 +356,6 @@ struct kvm_vcpu_arch {
		gfn_t last_pt_write_gfn;
		int last_pt_write_count;
		u64 *last_pte_updated;
		gfn_t last_pte_gfn;

		struct fpu guest_fpu;
		u64 xcr0;

arch/x86/kvm/mmu.c

+1 −21

Original line number	Diff line number	Diff line
		@@ -2207,11 +2207,6 @@ static int set_spte(struct kvm_vcpu vcpu, u64 sptep,
		if (set_mmio_spte(sptep, gfn, pfn, pte_access))
		return 0;

		/*
		* We don't set the accessed bit, since we sometimes want to see
		* whether the guest actually used the pte (in order to detect
		* demand paging).
		*/
		spte = PT_PRESENT_MASK;
		if (!speculative)
		spte \|= shadow_accessed_mask;
		@@ -2362,10 +2357,8 @@ static void mmu_set_spte(struct kvm_vcpu vcpu, u64 sptep,
		}
		}
		kvm_release_pfn_clean(pfn);
		if (speculative) {
		if (speculative)
		vcpu->arch.last_pte_updated = sptep;
		vcpu->arch.last_pte_gfn = gfn;
		}
		}

		static void nonpaging_new_cr3(struct kvm_vcpu *vcpu)
		@@ -3533,18 +3526,6 @@ static bool last_updated_pte_accessed(struct kvm_vcpu *vcpu)
		return !!(spte && (*spte & shadow_accessed_mask));
		}

		static void kvm_mmu_access_page(struct kvm_vcpu *vcpu, gfn_t gfn)
		{
		u64 *spte = vcpu->arch.last_pte_updated;

		if (spte
		&& vcpu->arch.last_pte_gfn == gfn
		&& shadow_accessed_mask
		&& !(*spte & shadow_accessed_mask)
		&& is_shadow_present_pte(*spte))
		set_bit(PT_ACCESSED_SHIFT, (unsigned long *)spte);
		}

		void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
		const u8 *new, int bytes,
		bool guest_initiated)
		@@ -3615,7 +3596,6 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
		++vcpu->kvm->stat.mmu_pte_write;
		trace_kvm_mmu_audit(vcpu, AUDIT_PRE_PTE_WRITE);
		if (guest_initiated) {
		kvm_mmu_access_page(vcpu, gfn);
		if (gfn == vcpu->arch.last_pt_write_gfn
		&& !last_updated_pte_accessed(vcpu)) {
		++vcpu->arch.last_pt_write_count;

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