On 9/23/22 7:35 AM, Peter Xu wrote:
Following commit 4802bf910eee9, add the other missing barrier when marking
the PFN as collected. This will also be required just like 4802bf910eee9
on weak ordering architectures like aarch64.
Cc: Marc Zyngier <m...@kernel.org>
Cc: Gavin Shan <gs...@redhat.com>
Cc: Paolo Bonzini <pbonz...@redhat.com>
Signed-off-by: Peter Xu <pet...@redhat.com>
---
accel/kvm/kvm-all.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
Reviewed-by: Gavin Shan <gs...@redhat.com>
diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
index 136c8eaed3..60a044048e 100644
--- a/accel/kvm/kvm-all.c
+++ b/accel/kvm/kvm-all.c
@@ -728,7 +728,11 @@ static bool dirty_gfn_is_dirtied(struct kvm_dirty_gfn *gfn)
static void dirty_gfn_set_collected(struct kvm_dirty_gfn *gfn)
{
- gfn->flags = KVM_DIRTY_GFN_F_RESET;
+ /*
+ * Write the flags after reading the entry. Should pair with another
+ * smp_load_acquire() in KVM when reset dirty rings.
+ */
+ qatomic_store_release(&gfn->flags, KVM_DIRTY_GFN_F_RESET);
}
/*
