xorg segfaults in libglx.so(__glXleaveServer+0x22)

I accidentally found this apport log. Please tell if you want the full coredump.

Here is gdb output from a core dump, with xserver-xorg-core-dbgsym installed.
#0 0xb7cbc17b in DRIDoBlockHandler (screenNum=0, blockData=0x0, pTimeout=0x0, pReadmask=0x0) at ../../../../hw/xfree86/dri/dri.c:1432
#1 0xb7c75946 in __glXDRIleaveServer () at ../../../GL/glx/glxdri.c:146
#2 0xb7c51c62 in __glXleaveServer () at ../../../GL/glx/glxext.c:461
#3 0xb7c522fe in __glXDispatch (client=0x829e408) at ../../../GL/glx/glxext.c:534
#4 0x0808690f in Dispatch () at ../../dix/dispatch.c:459
#5 0x0806e715 in main (argc=10, argv=0xbfbede34, envp=0x20) at ../../dix/main.c:479

Looking at the core dump data, I see that pDRIPriv is null, which is plausible if one looks at the DRI_SCREEN_PRIV macro. I am therefore trying to wrap all the pDRIPriv->... manipulations inside a "if (pDRIProv)" clause.

I also discovered an upstream bug with the same backtrace (and a similar fix reported working) although they talk about dual heads. I have just a simple laptop screen.
https://bugs.freedesktop.org/show_bug.cgi?id=8537

I made a debug build with this patch applied, and I am now stress-testing it with a gnomescreensaver-command -a / -d loop. No crash so far. On the other hand I don't see any occurence of this little debug message that I put into the patch. It should appear in Xorg.0.log, right?

The Edgy install of my parents was reported to crash xorg 80% of the times when starting OpenOffice.org. The backtrace from the xorg log they sent me looks familiar:

Backtrace:
0: /usr/X11R6/bin/X(xf86SigHandler+0x81) [0x80c3971]
1: [0xffffe420]
2: /usr/lib/xorg/modules/extensions/libglx.so [0xb7c3d946]
3: /usr/lib/xorg/modules/extensions/libglx.so(__glXleaveServer+0x22) [0xb7c19c62]
4: /usr/lib/xorg/modules/extensions/libglx.so [0xb7c1a2fe]
5: /usr/X11R6/bin/X(Dispatch+0x18f) [0x808693f]
6: /usr/X11R6/bin/X(main+0x485) [0x806e715]
7: /lib/tls/i686/cmov/libc.so.6(__libc_start_main+0xdc) [0xb7d5f8cc]
8: /usr/X11R6/bin/X(FontFileCompleteXLFD+0xa1) [0x806da51]

This is a Matrox G450 AGP with two heads, but only one is used.

Is this the same bug?

I have the same problem. Edgy, xserver-xorg-core 1.1.1ubuntu12

xorg log:
Backtrace:
0: /usr/X11R6/bin/X(xf86SigHandler+0x81) [0x80c3971]
1: [0xffffe420]
2: /usr/lib/libXfont.so.1(FontFileAddFontFile+0x252) [0xb7f180a2]
3: /usr/lib/libXfont.so.1(FontFileReadDirectory+0x83f) [0xb7f169df]
4: /usr/lib/libXfont.so.1(FontFileInitFPE+0x2f) [0xb7f1aa8f]
5: /usr/X11R6/bin/X [0x8087d68]
6: /usr/X11R6/bin/X(SetDefaultFontPath+0x79) [0x8087e69]
7: /usr/X11R6/bin/X(SetFontPath+0x2f) [0x8087ebf]
8: /usr/X11R6/bin/X(main+0x39e) [0x806e62e]
9: /lib/tls/i686/cmov/libc.so.6(__libc_start_main+0xdc) [0xb7d958cc]
10: /usr/X11R6/bin/X(FontFileCompleteXLFD+0xa1) [0x806da51]

Fatal server error:
Caught signal 8. Server aborting

It crashes in random moments, several times a day.

I backported the upstream fix to edgy, and you can download a test package here (it's a debug build):
http://tormod.webhop.org/linux/xorg-server/
Can Martijn and Magnes try it out? Otherwise I expect it to be fixed in xorg 7.2 which will release soon, and eventually enter feisty.

I will try to reproduce and test, but it's not my machine and I think meanwhile I changed something in the configuration that made this bug disappear (I seem to remember it was disabling direct rendering). I'll try to check through my parents.

After re-enabling DRI the bug could again be reproduced. I then compiled my own package with the same patches and we were not able to reproduce the bug anymore. So I think your backport fixes this. Thanks!

For the record, here is the one patch I used in my latest build.

Aflter installing xserver-xorg-core_1.1.1-0ubuntu12tormod2_i386.deb (or the tormod version) XOrg crashes almost immediately after start. I will attach log soon.

OK. I managed to run tormod2 version of xserver by reinstalling nvidia driver after installing it. I'll test if it's stable for several days and let you know.

My XOrg is stable now. No more crashes. The patch seems to work.

I suggest to have this backported or SRU'ed to Edgy, since it seems to touch several brands of cards. Usually the xserver does its own error trapping, so these crashes are not reported by apport.

Magnes, the "tormod2" version was a debug build without optimization. I rebuilt a normal version (based on the newer ubuntu12.1 version) with the patch from comment #13. You can download it from the same place, I called it *ubuntu12-1tormod_i386.deb

Of course, if you experience any crashes again, please install the debug version so that we can get useful stack traces.

It's a little strange. The normal version works but my system still isn't stable. I'm not sure if it's related to XOrg though - I need to give it more test. It may be Beryl related or truecrypt related or it may be sth with my hard drive configuration.
Sometimes XOrg (and sometimes even the whole system) crashes when I copy files (copying is slowing the system also when I copy files not from crypted partitions, but from my system 320GB seagate hard drive, so it's probably not truecrypt fault) - now it crashes only when I do many things at one time (for example start several programs at once or copy files in two applications, especially with Krusader which slows my system).
Although it's not that often and random as it was before I was using the patched version of xorg-server and there is NOTHING in the xorg log (as it hasn't crashed at all but was closed normally). Also my Firefox is crashing a lot. It's a little wearing. :(
My old Dapper installation on other partition (other hard drive) works fine.
(sorry for my English)

By writing that there is nothing in xorg log I ment that there is no indication of a crash - the old log looks exacly like the new log when I restart xorg.

And if you disable DRI you never get crashes, is that correct?

My patched versions does only address the issue that creates these segfaults with the above backtrace. If you don't get any backtrace any longer this issue is probably solved with the patch. Unfortunately there are many other bugs related to DRI in Xorg. What kind of graphics card do you have, by the way?

I suppose the patch works, because there are no more backtraces like those in the first posts. I have nvidia card (6200A), I will try to install newer drivers, maybe that will help (and read forum on nvidia.com, maybe there is some issue with the drivers). Thanks for the patch. It looks like this bug is solved but (as I stated above) my system is not in good shape, so I can't tell that for sure.

Confirmed on Matrox G450 AGP and Nvidia 6200A by comments, in addition to my S3 Savage TwisterK.

Please get this fixed and tested widely in Feisty first before requesting an SRU.

Makes sense. Is there something we can do to have this fixed in Feisty as soon as possible? (I am running the patched Edgy version in Feisty meanwhile.)

My system is very stable now with (also patched Edgy), other problems that I had were caused by bad CPU cooling. The patch works flawlessly.

Let's try to get this into feisty, while they decide on 7.2?

see debdiff.

patch seems to work fine here.

I've uploaded this fix for feisty. Thanks for tracking down the patch for it!

So, does anyone want to take care of the Edgy SRU? Please set a proper assignee and submit an SRU proposal according to the Policy.

Unsubscribing SRU team until then.

I'm getting what i believe is this same bug in an almost-up-to-date feisty (last update 8 march 2007). xorg dies with this in Xorg.0.log.old:
----
Backtrace:
0: /usr/bin/X(xf86SigHandler+0x81) [0x80c5d81]
1: [0xb7fbe420]

Fatal server error:
Caught signal 11. Server aborting
----
was dying mysteriously at 11 minute intervals, apparently becaue the screensaver was turned on (i switched to 'random' from 'display photos', and promptly forgot i'd done so). I can now reliably produce the crash by trying to start beryl, googleearth, various screensaver, glxinfo, or any other 3d programs. i'm using
xserver-xorg-core 2:1.2.0-3ubuntu3
nvidia 9746 (using nvidia installer)
millions of other possible packages.

3d worked fine on this computer for about 2 months until about 2 weeks ago (time frames approximate); maybe this is a regression in recent xorg releases?

would like to include apport bug traces but not sure how to do that manually; please suggest a method if you think such a trace would be of use.

forum activity in the last couple of weeks suggest the bug may still persist for other users too:

also i see some suggestions that the real upsteam bug for this issue may be:
https://bugs.freedesktop.org/show_bug.cgi?id=1753

matt

I'm reopening this one for Feisty... The fix in that upstream bug will be applied to our xorg-server-1.2.

hm, can't mark another upstream bug of the same component, oh well..

Matt: can you test this deb:

http://users.tkk.fi/~tjaalton/xorg72/new/xserver-xorg-core_1.2.0-3ubuntu4_i386.deb

It should be on the archive by Monday, but just to be sure that it actually fixes something :) Here's the debdiff:

http://users.tkk.fi/~tjaalton/xorg72/new/xorg-server.debdiff

Marking as fixed. Matt, if you still have problems, please file another bug.

hi timo, sorry not to have responded, but want to report that my
problems went away miraculously when i upgraded the nvidia driver --
this was before your recent update, so wasn't able to test the upgrade
as i was no longer able to trigger the crash. if i get similar results
again i'll file another bug. thanks so much for the swift update!

matt

On Thu, 2007-22-03 at 15:59 +0000, Timo Aaltonen wrote:
> Marking as fixed. Matt, if you still have problems, please file another
> bug.
>
> ** Changed in: xorg-server (Ubuntu)
> Status: In Progress => Fix Released
>
--
Matt Price
History Dept
University of Toronto
<email address hidden>

I'm having the same crash (when running anything that uses GLX)
 since the latest xorg update in edgy-security (1.1.1-0ubuntu12.2)

Backtrace:
 0: /usr/X11R6/bin/X(xf86SigHandler+0x81) [0x80c3971]
 1: [0xffffe420]

Fatal server error:
 Caught signal 11. Server aborting

-------------------------------------------------------------------------
This is with NVidia "restricted" drivers, worked fine before the update. I forced a "downgrade" to the old version and I still get the crash.
I'm going to try xserver-xorg-core_1.1.1-0ubuntu12.2tormod_i386.deb and/or reinstalling nvidia drivers. I will report back with the result of my testing.

ok, reinstalling the nvidia driver did the trick. It detected some files that were apparently overwritten by the recent xorg update from Ubuntu / Edgy Security. After installing the nvidia glx files everything seems to be back to normal.

Same problem on Feisty / Ati restricted drivers / Compiz. When a 3D screen-saver (GL Matrix) starts the X-server crashes and throws me back to the login screen.

If you don't have "glXleaveServer" in the backtrace, it's not useful to post in this bug (which has been closed). Please file a new bug.

Hi..
Sorry for my bad english........

I have a ATI RADEON 9600 with restricted driver installed.
I use BERYL and it work fine but my X sometimes crash without advise and session restart from the login window.

Where i can read cause of restart?

Please help my..
Denis

Denis, look in /var/log/Xorg.0.log (or /var/log/Xorg.0.log.old if an X session has restarted). Please file a new bug for your problem.

This is still an issue in gutsy, xorg 7.3

I'd guess the patch has been dropped.

We can re-apply the same patch, if we can verify it's the same bug. Sarah, can you crash X and post a fresh backtrace from Xorg.0.log (or Xorg.0.log.old) showing the backtrace? It sounds like this patch is relevant only if "glXleaveServer" is present in the backtrace. If it isn't, then this is a new bug we should report upstream ASAP.

Sarah,

I've re-rolled a new xorg-server package with this patch re-enabled. If you can confirm that the backtrace is showing "glXleaveServer", please try this new xorg-server and verify that it resolves the problem, and we'll push this out into Gutsy.

Thanks,
Bryce

Attempting to make it crash again.

This seems to be like pets and children - they wont show the symptoms when there's someone around to help them.

grrr.

Will respond back when I find something, though.

I cant seem to reproduce this. Marking as fixed again.