On 2019/3/5 21:09, Gerd Hoffmann wrote:
> vnc aborts display update jobs on video mode switches and page flips.
> That can cause vnc update stalls in case an unfinished vnc job gets
> aborted. The vnc client will never receive the requested update then.
> Fix that by copying the state from job_update back to update in that
> case.
>
> Reports complain about stalls with two or more clients being connected
> at the same time, on some but not all connections. I suspect it can
> also happen with a single connection, multiple connections only make
> this more much likely to happen.
>
> Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1662260
> Reported-by: Ying Fang <fangying1@huawei.com>
> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Ying Fang <fangying1@huawei.com>
> ---
> ui/vnc.c | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/ui/vnc.c b/ui/vnc.c
> index da4a21d4ce94..2f2ab62fcf71 100644
> --- a/ui/vnc.c
> +++ b/ui/vnc.c
> @@ -700,6 +700,12 @@ static void vnc_abort_display_jobs(VncDisplay *vd)
> }
> QTAILQ_FOREACH(vs, &vd->clients, next) {
> vnc_lock_output(vs);
> + if (vs->update == VNC_STATE_UPDATE_NONE &&
> + vs->job_update != VNC_STATE_UPDATE_NONE) {
> + /* job aborted before completion */
> + vs->update = vs->job_update;
> + vs->job_update = VNC_STATE_UPDATE_NONE;
> + }
> vs->abort = false;
> vnc_unlock_output(vs);
> }
>