Re: [PATCH 1/7] vhost_user: Reset vq enable flag in vu_cleanup()

On Fri, Jul 31, 2026 at 06:46:22PM +0200, Laurent Vivier wrote:

vu_cleanup() resets most virtqueue state (started, notification, file descriptors) but does not reset the enable flag. After a QEMU disconnect and reconnect, the stale enable flag causes vu_set_vring_enable_exec() to hit its early return check (vq->enable == enable), skipping the threading_start_thread() call and leaving the worker thread stopped.

Reset vq->enable to false in vu_cleanup() alongside the other virtqueue state.

Signed-off-by: Laurent Vivier

Reviewed-by: David Gibson AFAICT it would make sense to apply this fix immediately, independent of the rest of the series.

--- vhost_user.c | 1 + 1 file changed, 1 insertion(+)

diff --git a/vhost_user.c b/vhost_user.c index 9e382c21f963..8ba3949e4e9d 100644 --- a/vhost_user.c +++ b/vhost_user.c @@ -1083,6 +1083,7 @@ void vu_cleanup(struct vu_dev *vdev) struct vu_virtq *vq = &vdev->vq[i];

vq->started = false; + vq->enable = false; vq->notification = true;

if (vq->call_fd != -1) { -- 2.54.0

-- David Gibson (he or they) | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you, not the other way | around. http://www.ozlabs.org/~dgibson