Xorg freezes when running strace alarm-clock

[Jo-Erlend Schinstad]

In Jaunty, X freezes from time to time, but it does freeze consistently whenever I run alarm-clock. I don't think the problem is with alarm-clock, really, but it's a good symptom.

To reproduce:

* Install apt://alarm-clock.
* Run it.
* If X doesn't freeze already,
* create a new alarm.

X will now freeze, except for mouse.

[lspci]
00:00.0 Host bridge [0600]: Intel Corporation 440FX - 82441FX PMC [Natoma] [8086:1237] (rev 02)
00:02.0 VGA compatible controller [0300]: InnoTek Systemberatung GmbH VirtualBox Graphics Adapter [80ee:beef]
     Subsystem: Advanced Micro Devices [AMD] 79c970 [PCnet32 LANCE] [1022:2000]

[Andres Mujica (andres.mujica)]

Architecture: i386
DistroRelease: Ubuntu 9.04
ProcEnviron:
 SHELL=/bin/bash
 PATH=(custom, user)
 LANG=es_ES.UTF-8
Uname: Linux 2.6.28-11-generic i686
UserGroups: adm admin audio cdrom dialout dip floppy fuse lpadmin netdev plugdev powerdev pulse-access pulse-rt sambashare scanner vboxusers video

[Andres Mujica (andres.mujica)]

Architecture: i386
Dependencies:

DistroRelease: Ubuntu 9.04
Package: linux None [modified: /var/lib/dpkg/info/linux.list]
PackageArchitecture: i386
ProcEnviron:
 SHELL=/bin/bash
 PATH=(custom, user)
 LANG=es_ES.UTF-8
Uname: Linux 2.6.28-11-generic i686
UserGroups: adm admin audio cdrom dialout dip floppy fuse lpadmin netdev plugdev powerdev pulse-access pulse-rt sambashare scanner vboxusers video

[Jo-Erlend Schinstad (joerlend.schinstad-deactivatedaccount)]

Architecture: i386
DistroRelease: Ubuntu 9.04
Package: alarm-clock 0.9.18-3
PackageArchitecture: all
ProcEnviron:
 SHELL=/bin/bash
 LANG=nb_NO.UTF-8
Uname: Linux 2.6.28-11-generic i686
UserGroups: adm admin audio cdrom dialout dip fax fuse lpadmin netdev plugdev sambashare vboxusers video

[Jo-Erlend Schinstad (joerlend.schinstad-deactivatedaccount)]

Architecture: i386
DistroRelease: Ubuntu 9.04
Package: xserver-xorg 1:7.4~5ubuntu18
PackageArchitecture: i386
ProcEnviron:
 SHELL=/bin/bash
 LANG=nb_NO.UTF-8
ProcVersion: Linux version 2.6.28-11-generic (buildd@rothera) (gcc version 4.3.3 (Ubuntu 4.3.3-5ubuntu4) ) #41-Ubuntu SMP Wed Apr 8 04:38:53 UTC 2009
Uname: Linux 2.6.28-11-generic i686
UserGroups: adm admin audio cdrom dialout dip fax fuse lpadmin netdev plugdev sambashare vboxusers video

[Andres Mujica (andres.mujica)]

Architecture: i386
Dependencies:

DistroRelease: Ubuntu 9.04
Package: linux None [modified: /var/lib/dpkg/info/linux.list]
PackageArchitecture: i386
ProcEnviron:
 SHELL=/bin/bash
 PATH=(custom, user)
 LANG=es_ES.UTF-8
Uname: Linux 2.6.28-11-generic i686
UserGroups: adm admin audio cdrom dialout dip floppy fuse lpadmin netdev plugdev powerdev pulse-access pulse-rt sambashare scanner vboxusers video

[Jo-Erlend Schinstad (joerlend.schinstad-deactivatedaccount)]

The same thing happens in jaunty running in a virtualbox vm.

[Jo-Erlend Schinstad (joerlend.schinstad-deactivatedaccount)]

Architecture: i386
DistroRelease: Ubuntu 9.04
Package: xserver-xorg 1:7.4~5ubuntu18
PackageArchitecture: i386
ProcEnviron:
 SHELL=/bin/bash
 LANG=nb_NO.UTF-8
ProcVersion: Linux version 2.6.28-11-generic (buildd@rothera) (gcc version 4.3.3 (Ubuntu 4.3.3-5ubuntu4) ) #41-Ubuntu SMP Wed Apr 8 04:38:53 UTC 2009
Uname: Linux 2.6.28-11-generic i686
UserGroups: adm admin cdrom dialout lpadmin plugdev sambashare

[Jo-Erlend Schinstad (joerlend.schinstad-deactivatedaccount)]

Coincidentally, I tried running "strace gcalctool", which yields the same results.

[Andres Mujica (andres.mujica)]

after some testing it seems not related to X nor the kernel, as logging remotely via ssh and killing alarm-clock recovers the system from the lock.

Probably is a focus thing with alarm clock.

[Andres Mujica (andres.mujica)]

However there's a X freeze bug going on. The metabug at this time is bug #358033

[Andres Mujica (andres.mujica)]

sorry bug #359392

[Bryce Harrington (bryce)]

Actually, I'd like to keep this one open against X.org. While it seems to be localized to alarm-clock, I don't like that a single userspace application can freeze up X so hard, and I suspect the issue is something distinct from #359392. Even though there's a straightforward workaround, I'd prefer to figure out why this is happening and make X not permit it.

Thanks for finding the bug and filing it. I don't think we'll worry about it for Jaunty but I'd like to get it looked into for Karmic if there's time.

[Jo-Erlend Schinstad (joerlend.schinstad-deactivatedaccount)]

Ok, but the same thing is happening with lots of other applications, only not so consistently. Well, the symptoms are identical, anyway. I really don't know the cause.

[Alexey Osipov (lion-simba)]

Confirm that bug on NVIDIA 7600 GT.
Same random X freezes in Jaunty.
Same stable X freeze when I run alarm-clock.

[Nick B. (futurepilot)]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

I can reproduce this with a Nvidia card as well by just running
alarm-clock. I don't think it's specific to the Intel cards. It's not
a hard lockup, I can still move the mouse and the keyboard is
responsive; I can still switch to a console and kill it to unfreeze X.
I've also noticed that I get this same exact kind of "soft" lockup
when running strace on just about any arbitrary application. I've been
trying to get an strace on Nautilus for another issue and almost every
time I run strace, X goes into one of these soft lockups and I have to
go to a console to kill the application.

01:00.0 VGA compatible controller: nVidia Corporation GeForce 8400M GS
(rev a1)
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.9 (GNU/Linux)

iEYEARECAAYFAkntPvMACgkQAGHzB9Tvw4yfbwCfRjWcUT4kGybeIWLAeeluIDjr
vWsAoLBUAUJ2L7RYFVKcuheL8DhSBxsY
=BIsb
-----END PGP SIGNATURE-----