We need make sure there's no reference on the map before trying to mark set dirty pages. Reported-by: Michael S. Tsirkin <mst@xxxxxxxxxx> Fixes: 7f466032dc9e ("vhost: access vq metadata through kernel virtual address") Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx> --- drivers/vhost/vhost.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 57bfbb60d960..6650a3ff88c1 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -410,14 +410,13 @@ static void vhost_invalidate_vq_start(struct vhost_virtqueue *vq, ++vq->invalidate_count; map = vq->maps[index]; - if (map) { - vhost_set_map_dirty(vq, map, index); + if (map) vq->maps[index] = NULL; - } spin_unlock(&vq->mmu_lock); if (map) { vhost_vq_sync_access(vq); + vhost_set_map_dirty(vq, map, index); vhost_map_unprefetch(map); } } -- 2.18.1