[11/12] KVM: arm64: Support disable hw dirty log after enable

Commit Message

zhukeqian June 16, 2020, 9:35 a.m. UTC

We should clear DBM bit of all PTEs and flush TLB, then sync dirty log,
which promise we won't miss any dirty status set by hardware.

Signed-off-by: Keqian Zhu <[e-mail]>
---
 arch/arm64/kvm/arm.c | 6 ++++++
 1 file changed, 6 insertions(+)

Patch

diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 92f0b40a30fa..76cab4c0b5a6 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -93,6 +93,12 @@  int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
 			r = -EINVAL;
 		} else {
 			r = 0;
+			if (kvm->arch.hw_dirty_log && !cap->args[0]) {
+				mutex_lock(&kvm->slots_lock);
+				kvm_mmu_clear_dbm_all(kvm);
+				kvm_mmu_sync_dirty_log_all(kvm);
+				mutex_unlock(&kvm->slots_lock);
+			}
 			kvm->arch.hw_dirty_log = cap->args[0];
 		}
 		break;