On Wed, Jan 29, 2020 at 04:19:05AM -0500, Frediano Ziglio wrote: > > > > On Thu, Jan 23, 2020 at 11:54:50AM -0500, Cole Robinson wrote: > > > Hi all, > > > > > > For the past year+ we have had a steady trickle of virt-manager X11 > > > threading crashes. This is the f31 bug I've duped all the other ones > > > too, but there were a handful that were auto closed by Fedora > > > end-of-life bug cleanup: > > > https://bugzilla.redhat.com/show_bug.cgi?id=1756065 > > > > > > The message that goes along with this is: > > > > > > [xcb] Unknown sequence number while processing queue > > > [xcb] Most likely this is a multi-threaded client and XInitThreads has > > > not been called > > > [xcb] Aborting, sorry about that. > > > remote-viewer: xcb_io.c:263: poll_for_event: Assertion > > > `!xcb_xlib_threads_sequence_lost' failed. > > > Aborted (core dumped) > > > > > > That may not apply to all the poll_for_error() bugs but it's most of the > > > ones I have dug into. > > > > > > I figured there was some threading issue in virt-manager and I was > > > mostly ignoring the bugs until I found time to try and diagnose. I'm not > > > really finding anything in virt-manager though, and some similar issues > > > make me think maybe this is spice-gtk or something lower. > > > > > > This user can reproduce the same error with remote-viewer + spice + X11 > > > ssh forwarding: https://bugzilla.redhat.com/show_bug.cgi?id=1758384 > > > > > > This user can reproduce the virt-manager crash multiple times a day, and > > > it's always when interacting with a spice-gtk console: > > > https://bugzilla.redhat.com/show_bug.cgi?id=1792576 > > > > > > Anyone have any ideas how to debug this further? What spice-gtk > > > debugging info would be helpful? > > > > FWIW if you're trying to reproduce this yourself, the key factor here > > is that they are using X11, not Wayland. Given that Fedora defaults > > to Wayland this likely explains why only certain people are seeing > > it. > > > > The error message strongly suggests that there are multiple threads > > making X11 calls at the same time. This in turn means multiple threads > > are making GTK calls at the same time, and this is expressly forbidden > > by GTK - GTK APIs are only permitted to be invoked from the main thread > > which runs the event loop. > > > > It does look like a probable spice issue given the common crash in > > remote-viewer, as aside from GTK itself and GTK-VNC, that's the only > > UI library both apps use. > > > > Regards, > > Daniel > > Hi, > found the root cause, a bug in libX11, see updates to > https://bugzilla.redhat.com/show_bug.cgi?id=1758384. > As it's not specifically related to virt-manager/virt-viewer which > Product/Component should the bug moved to? This is an upstream reported bug, so moving to Fedora/libX11 is a good first choice. I'd probably *also* clone it to RHEL-8/libX11 as that will increase the likelihood of someone caring enough to fix it. Perhaps also link both BZ to a upstream libX11 bug tracker ? Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :| _______________________________________________ Spice-devel mailing list Spice-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/spice-devel