It simplifies validation of gfn_to_hva_cache to make it less error prone per the discussion at https://lore.kernel.org/all/4e29402770a7a254a1ea8ca8165af641ed0832ed.camel@xxxxxxxxxxxxx. Signed-off-by: Metin Kaya <metikaya@xxxxxxxxxxxx> --- arch/x86/kvm/x86.c | 26 ++++++++++++++------------ 1 file changed, 14 insertions(+), 12 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 43a6a7efc6ec..07d368dc69ad 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -3425,11 +3425,22 @@ void kvm_service_local_tlb_flush_requests(struct kvm_vcpu *vcpu) } EXPORT_SYMBOL_GPL(kvm_service_local_tlb_flush_requests); +static inline bool kvm_gfn_to_hva_cache_valid(struct kvm *kvm, + struct gfn_to_hva_cache *ghc, + gpa_t gpa) +{ + struct kvm_memslots *slots = kvm_memslots(kvm); + + return !unlikely(slots->generation != ghc->generation || + gpa != ghc->gpa || + kvm_is_error_hva(ghc->hva) || + !ghc->memslot); +} + static void record_steal_time(struct kvm_vcpu *vcpu) { struct gfn_to_hva_cache *ghc = &vcpu->arch.st.cache; struct kvm_steal_time __user *st; - struct kvm_memslots *slots; gpa_t gpa = vcpu->arch.st.msr_val & KVM_STEAL_VALID_BITS; u64 steal; u32 version; @@ -3445,11 +3456,7 @@ static void record_steal_time(struct kvm_vcpu *vcpu) if (WARN_ON_ONCE(current->mm != vcpu->kvm->mm)) return; - slots = kvm_memslots(vcpu->kvm); - - if (unlikely(slots->generation != ghc->generation || - gpa != ghc->gpa || - kvm_is_error_hva(ghc->hva) || !ghc->memslot)) { + if (!kvm_gfn_to_hva_cache_valid(vcpu->kvm, ghc, gpa)) { /* We rely on the fact that it fits in a single page. */ BUILD_BUG_ON((sizeof(*st) - 1) & KVM_STEAL_VALID_BITS); @@ -4729,7 +4736,6 @@ static void kvm_steal_time_set_preempted(struct kvm_vcpu *vcpu) { struct gfn_to_hva_cache *ghc = &vcpu->arch.st.cache; struct kvm_steal_time __user *st; - struct kvm_memslots *slots; static const u8 preempted = KVM_VCPU_PREEMPTED; gpa_t gpa = vcpu->arch.st.msr_val & KVM_STEAL_VALID_BITS; @@ -4756,11 +4762,7 @@ static void kvm_steal_time_set_preempted(struct kvm_vcpu *vcpu) if (unlikely(current->mm != vcpu->kvm->mm)) return; - slots = kvm_memslots(vcpu->kvm); - - if (unlikely(slots->generation != ghc->generation || - gpa != ghc->gpa || - kvm_is_error_hva(ghc->hva) || !ghc->memslot)) + if (!kvm_gfn_to_hva_cache_valid(vcpu->kvm, ghc, gpa)) return; st = (struct kvm_steal_time __user *)ghc->hva; -- 2.37.1
