From: Takuya Yoshikawa <yoshikawa.takuya@xxxxxxxxxxxxx> (cherry picked from commit 565f3be2174611f364405bbea2d86e153c2e7e78 Other threads may process the same page in that small window and skip TLB flush and then return before these functions do flush. Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@xxxxxxxxxxxxx> Signed-off-by: Marcelo Tosatti <mtosatti@xxxxxxxxxx> Signed-off-by: Avi Kivity <avi@xxxxxxxxxx> --- virt/kvm/kvm_main.c | 19 ++++++++++--------- 1 files changed, 10 insertions(+), 9 deletions(-) diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index e401c1b..9ffac2e 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -289,15 +289,15 @@ static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn, */ idx = srcu_read_lock(&kvm->srcu); spin_lock(&kvm->mmu_lock); + kvm->mmu_notifier_seq++; need_tlb_flush = kvm_unmap_hva(kvm, address) | kvm->tlbs_dirty; - spin_unlock(&kvm->mmu_lock); - srcu_read_unlock(&kvm->srcu, idx); - /* we've to flush the tlb before the pages can be freed */ if (need_tlb_flush) kvm_flush_remote_tlbs(kvm); + spin_unlock(&kvm->mmu_lock); + srcu_read_unlock(&kvm->srcu, idx); } static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn, @@ -335,12 +335,12 @@ static void kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn, for (; start < end; start += PAGE_SIZE) need_tlb_flush |= kvm_unmap_hva(kvm, start); need_tlb_flush |= kvm->tlbs_dirty; - spin_unlock(&kvm->mmu_lock); - srcu_read_unlock(&kvm->srcu, idx); - /* we've to flush the tlb before the pages can be freed */ if (need_tlb_flush) kvm_flush_remote_tlbs(kvm); + + spin_unlock(&kvm->mmu_lock); + srcu_read_unlock(&kvm->srcu, idx); } static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn, @@ -378,13 +378,14 @@ static int kvm_mmu_notifier_clear_flush_young(struct mmu_notifier *mn, idx = srcu_read_lock(&kvm->srcu); spin_lock(&kvm->mmu_lock); - young = kvm_age_hva(kvm, address); - spin_unlock(&kvm->mmu_lock); - srcu_read_unlock(&kvm->srcu, idx); + young = kvm_age_hva(kvm, address); if (young) kvm_flush_remote_tlbs(kvm); + spin_unlock(&kvm->mmu_lock); + srcu_read_unlock(&kvm->srcu, idx); + return young; } -- 1.7.6.4 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
