From edb298c663fccad65fe99fcec6a4f96cc344520d Mon Sep 17 00:00:00 2001 From: Maxim Levitsky Date: Tue, 10 Aug 2021 23:52:39 +0300 Subject: KVM: x86/mmu: bump mmu notifier count in kvm_zap_gfn_range This together with previous patch, ensures that kvm_zap_gfn_range doesn't race with page fault running on another vcpu, and will make this page fault code retry instead. This is based on a patch suggested by Sean Christopherson: https://lkml.org/lkml/2021/7/22/1025 Suggested-by: Sean Christopherson Signed-off-by: Maxim Levitsky Message-Id: <20210810205251.424103-5-mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini --- virt/kvm/kvm_main.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'virt') diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 3e81b5d8b709..8563d9b725af 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -610,7 +610,7 @@ static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn, kvm_handle_hva_range(mn, address, address + 1, pte, kvm_set_spte_gfn); } -static void kvm_inc_notifier_count(struct kvm *kvm, unsigned long start, +void kvm_inc_notifier_count(struct kvm *kvm, unsigned long start, unsigned long end) { /* @@ -638,6 +638,7 @@ static void kvm_inc_notifier_count(struct kvm *kvm, unsigned long start, max(kvm->mmu_notifier_range_end, end); } } +EXPORT_SYMBOL_GPL(kvm_inc_notifier_count); static int kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn, const struct mmu_notifier_range *range) @@ -672,7 +673,7 @@ static int kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn, return 0; } -static void kvm_dec_notifier_count(struct kvm *kvm, unsigned long start, +void kvm_dec_notifier_count(struct kvm *kvm, unsigned long start, unsigned long end) { /* @@ -689,6 +690,8 @@ static void kvm_dec_notifier_count(struct kvm *kvm, unsigned long start, */ kvm->mmu_notifier_count--; } +EXPORT_SYMBOL_GPL(kvm_dec_notifier_count); + static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn, const struct mmu_notifier_range *range) -- cgit