diff options
| author | Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp> | 2012-02-10 15:28:31 +0900 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2012-05-31 00:43:09 +0100 |
| commit | 51155201f92e585d40d8921893a508e8b99b2d0e (patch) | |
| tree | 752f5f5f25c940166d10d965f6ad5ba35da72e46 | |
| parent | 52c6b95f8a2edaff98b779f15b2f4d69b61b18b9 (diff) | |
KVM: mmu_notifier: Flush TLBs before releasing mmu_lock
(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@oss.ntt.co.jp>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
| -rw-r--r-- | 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 e401c1b118e9..9ffac2e0d16f 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; } |