KVM: MMU: Flush tlbs after clearing write permission when accessing dirty log

(cherry picked from commit 171d595d3b3254b9a952af8d1f6965d2e85dcbaa)

Otherwise, the cpu may allow writes to the tracked pages, and we lose
some display bits or fail to migrate correctly.

Signed-off-by: Avi Kivity <avi@qumranet.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 32aa0b814842df0649f9d397b2eb0d8f2705e641..4c944941b0aa50eb1e6651fb366f7d64e13a4435 100644 (file)
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -2069,6 +2069,7 @@ void kvm_mmu_slot_remove_write_access(struct kvm *kvm, int slot)
                        if (pt[i] & PT_WRITABLE_MASK)
                                pt[i] &= ~PT_WRITABLE_MASK;
        }
+       kvm_flush_remote_tlbs(kvm);
        spin_unlock(&kvm->mmu_lock);
 }