F26: particular keystrokes cause Xorg to freeze momentarily, looking for debugging suggestions

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hello fellow Fedora users,

I've been using the same Fedora installation on my desktop for the last 4 years, but for the first time I'm completely stumbled with a bug after upgrading from Fedora Workstation 25 to 26.

When I press the slash/question-mark (on a PT-BR keyboard) key while focused into a window, or when pressing backspace to erase that slash immediately afterwards, X11 will freeze for about a second consuming 100% CPU. No other key causes the same behavior, not even the slash key from the numeric keypad. I can observe the issue in GTK2, GTK3, Qt and custom applications (such as Chrome and Firefox), but I cannot reproduce the behavior when sending inputs to `xev` for observation. Even GDM is afflicted when typing my user password, before ever having logged in.

Given the bizarre and extremely specific nature of the issue, my first suspects are input-related software such as ibus, libinput or Xorg itself. Using different ibus settings, and even attempting to disable it (by setting XMODIFIERS=@im=none) didn't seem to have any effect. libinput doesn't seem like a good candidate, as raw events captured by `xev` don't trigger the issue.

I profiled Xorg using `perf` but could not see any clues to what the problem is. I generated a flame-graph [1] (source data at [2]), but most of the symbols seem to be missing, probably courtesy of the NVIDIA proprietary driver.

I'm not even sure to which software to report this bug. Is anyone experiencing anything similar, or has any suggestions for ways to debug to get to the core of the problem?

[1]: https://linux.ime.usp.br/~danielqm/f26-x11-perf/xorg.svg
[2]: https://linux.ime.usp.br/~danielqm/f26-x11-perf/xorg.folded
--

Thanks in advance,
Daniel

_______________________________________________
users mailing list -- users@xxxxxxxxxxxxxxxxxxxxxxx
To unsubscribe send an email to users-leave@xxxxxxxxxxxxxxxxxxxxxxx



[Index of Archives]     [Older Fedora Users]     [Fedora Announce]     [Fedora Package Announce]     [EPEL Announce]     [EPEL Devel]     [Fedora Magazine]     [Fedora Summer Coding]     [Fedora Laptop]     [Fedora Cloud]     [Fedora Advisory Board]     [Fedora Education]     [Fedora Security]     [Fedora Scitech]     [Fedora Robotics]     [Fedora Infrastructure]     [Fedora Websites]     [Anaconda Devel]     [Fedora Devel Java]     [Fedora Desktop]     [Fedora Fonts]     [Fedora Marketing]     [Fedora Management Tools]     [Fedora Mentors]     [Fedora Package Review]     [Fedora R Devel]     [Fedora PHP Devel]     [Kickstart]     [Fedora Music]     [Fedora Packaging]     [Fedora SELinux]     [Fedora Legal]     [Fedora Kernel]     [Fedora OCaml]     [Coolkey]     [Virtualization Tools]     [ET Management Tools]     [Yum Users]     [Yosemite News]     [Gnome Users]     [KDE Users]     [Fedora Art]     [Fedora Docs]     [Fedora Sparc]     [Libvirt Users]     [Fedora ARM]

  Powered by Linux