From: Mihai Donțu <mdontu@xxxxxxxxxxxxxxx> KVM doesn't normally need to keep track that closely to page access bits, however for the introspection subsystem this is essential. Suggested-by: Paolo Bonzini <pbonzini@xxxxxxxxxx> Link: https://marc.info/?l=kvm&m=149804987417131&w=2 CC: Sean Christopherson <sean.j.christopherson@xxxxxxxxx> Signed-off-by: Mihai Donțu <mdontu@xxxxxxxxxxxxxxx> Signed-off-by: Adalbert Lazăr <alazar@xxxxxxxxxxxxxxx> --- arch/x86/kvm/mmu.c | 21 +++++++++++++++++++-- 1 file changed, 19 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 9eaf6cc776a9..810e3e5bd575 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -2491,6 +2491,20 @@ static void clear_sp_write_flooding_count(u64 *spte) __clear_sp_write_flooding_count(sp); } +static unsigned int kvm_mmu_page_track_acc(struct kvm_vcpu *vcpu, gfn_t gfn, + unsigned int acc) +{ + if (kvm_page_track_is_active(vcpu, gfn, KVM_PAGE_TRACK_PREREAD)) + acc &= ~ACC_USER_MASK; + if (kvm_page_track_is_active(vcpu, gfn, KVM_PAGE_TRACK_PREWRITE) || + kvm_page_track_is_active(vcpu, gfn, KVM_PAGE_TRACK_WRITE)) + acc &= ~ACC_WRITE_MASK; + if (kvm_page_track_is_active(vcpu, gfn, KVM_PAGE_TRACK_PREEXEC)) + acc &= ~ACC_EXEC_MASK; + + return acc; +} + static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu, gfn_t gfn, gva_t gaddr, @@ -2511,7 +2525,7 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu, role.direct = direct; if (role.direct) role.cr4_pae = 0; - role.access = access; + role.access = kvm_mmu_page_track_acc(vcpu, gfn, access); if (!vcpu->arch.mmu->direct_map && vcpu->arch.mmu->root_level <= PT32_ROOT_LEVEL) { quadrant = gaddr >> (PAGE_SHIFT + (PT64_PT_BITS * level)); @@ -3234,7 +3248,10 @@ static int __direct_map(struct kvm_vcpu *vcpu, int write, int map_writable, for_each_shadow_entry(vcpu, (u64)gfn << PAGE_SHIFT, iterator) { if (iterator.level == level) { - emulate = mmu_set_spte(vcpu, iterator.sptep, ACC_ALL, + unsigned int acc = kvm_mmu_page_track_acc(vcpu, gfn, + ACC_ALL); + + emulate = mmu_set_spte(vcpu, iterator.sptep, acc, write, level, gfn, pfn, prefault, map_writable); direct_pte_prefetch(vcpu, iterator.sptep);
