Possibly related to the two MR 5043 patches carried in 50.1-0ubuntu2.5. Since that upload went live (first boot 2026-10-31), GTK4 clients on my machine crash with SIGSEGV in gdk_surface_handle_event() (gdk/gdksurface.c:2993) on resume, from a dispatched event whose surface is NULL. The Wayland backend builds tablet pad events with seat->keyboard_focus as their surface, so if mutter broadcasts wp_tablet_pad_group.mode_switch when a pad gains focus on registration, and the client has not yet handled wl_keyboard.enter, GTK dereferences NULL.
Crash frequency by running version: mutter 2.2 / kernel 7.0.0-31 36 resumes, 4 crashes mutter 2.4 / kernel 7.0.0-34/38 84 resumes, 0 crashes mutter 2.5 / kernel 7.0.0-42 6 resumes, 5 crashes Hardware is a HUION tablet (256c:006d) with a pad that exposes a dial and a touch strip. One of the five crashes happened during a USB re-enumeration with no suspend involved. Pads are handled by the generic zwp_tablet_pad_* implementation in mutter and GTK, with no vendor code above the kernel driver, and mode_switch is broadcast for any pad group. So I would expect this path to be reachable with Wacom or any other pad, not just Huion - although I have no Wacom hardware here to confirm it. Caveat: 7.0.0-42 landed in the same upload, so the kernel is not excluded. But the pad focus broadcast is mutter's timing, and the two 2.5 patches that rework tablet tool surface accounting are the obvious suspects. Details: https://bugs.launchpad.net/bugs/2172827 Not asking for a revert - the guard belongs in GTK. Just an FYI. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2169504 Title: Wacom pen can't drag-and-drop in GNOME 50 Wayland; works in Xfce (X11) To manage notifications about this bug go to: https://bugs.launchpad.net/mutter/+bug/2169504/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
