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

From: Keqian Zhu
Date: Tue Jun 16 2020 - 05:36:36 EST


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 <zhukeqian1@xxxxxxxxxx>
---
arch/arm64/kvm/arm.c | 6 ++++++
1 file changed, 6 insertions(+)

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;
--
2.19.1