vhost backend sends host notification for every VQ. If backend creates
VQs in parallel, the VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG may
arrive to QEMU in different order than incremental queue index order.
For example VQ 1's message arrive earlier than VQ 0's:
After alloc VhostUserHostNotifier for VQ 1. GPtrArray becomes
[ nil, VQ1 pointer ]
After alloc VhostUserHostNotifier for VQ 0. GPtrArray becomes
[ VQ0 pointer, nil, VQ1 pointer ]
This is wrong. fetch_notifier will return NULL for VQ 1 in
vhost_user_get_vring_base, causes host notifier miss removal(leak).
The fix is to remove current element from GPtrArray, make the right
position for element to insert.
Fixes: 503e355465 ("virtio/vhost-user: dynamically assign
VhostUserHostNotifiers")
Signed-off-by: Yajun Wu <yaj...@nvidia.com>
Acked-by: Parav Pandit <pa...@nvidia.com>
---
hw/virtio/vhost-user.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
index 03415b6c95..d256ce589b 100644
--- a/hw/virtio/vhost-user.c
+++ b/hw/virtio/vhost-user.c
@@ -1543,6 +1543,11 @@ static VhostUserHostNotifier
*fetch_or_create_notifier(VhostUserState *u,
n = g_ptr_array_index(u->notifiers, idx);
if (!n) {
+ /*
+ * In case notification arrive out-of-order,
+ * make room for current index.
+ */
+ g_ptr_array_remove_index(u->notifiers, idx);
n = g_new0(VhostUserHostNotifier, 1);
n->idx = idx;
g_ptr_array_insert(u->notifiers, idx, n);
--
2.27.0
