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KVM: mmu_notifier: Flush TLBs before releasing mmu_lock

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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>
This commit is contained in:
Takuya Yoshikawa 2012-02-10 15:28:31 +09:00 committed by Avi Kivity
parent db3fe4eb45
commit 565f3be217
1 changed files with 10 additions and 9 deletions
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19
virt/kvm/kvm_main.c
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@ -289,15 +289,15 @@ static void kvm_mmu_notifier_invalidate_page(struct mmu_notifier *mn,
*/ */
idx = srcu_read_lock(&kvm->srcu); idx = srcu_read_lock(&kvm->srcu);
spin_lock(&kvm->mmu_lock); spin_lock(&kvm->mmu_lock);
kvm->mmu_notifier_seq++; kvm->mmu_notifier_seq++;
need_tlb_flush = kvm_unmap_hva(kvm, address) | kvm->tlbs_dirty; 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 */ /* we've to flush the tlb before the pages can be freed */
if (need_tlb_flush) if (need_tlb_flush)
kvm_flush_remote_tlbs(kvm); 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, 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) for (; start < end; start += PAGE_SIZE)
need_tlb_flush |= kvm_unmap_hva(kvm, start); need_tlb_flush |= kvm_unmap_hva(kvm, start);
need_tlb_flush |= kvm->tlbs_dirty; 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 */ /* we've to flush the tlb before the pages can be freed */
if (need_tlb_flush) if (need_tlb_flush)
kvm_flush_remote_tlbs(kvm); 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, 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); idx = srcu_read_lock(&kvm->srcu);
spin_lock(&kvm->mmu_lock); 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) if (young)
kvm_flush_remote_tlbs(kvm); kvm_flush_remote_tlbs(kvm);
spin_unlock(&kvm->mmu_lock);
srcu_read_unlock(&kvm->srcu, idx);
return young; return young;
} }