Xorg crashes with SIG 11 in FindGlyphRef

Hi fuchs,

Please attach the output of `lspci -vvnn` and `dmesg`, and attach your /var/log/Xorg.0.log (and maybe Xorg.0.log.old) file from after reproducing this issue. If you're using a custom /etc/X11/xorg.conf please attach that as well.

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Hello Bryce,

I will update the bug report tomorrow, as for today I don't have access to this system anymore.

As an update in general:

I tried to track down the problem, and as it seems to be font rendering (glyph cache), I tried a few options there.

The problem is only reproducible when

1) Font Antialiasing is on for Qt/KDE
2) Specific fonts are used (tried: Serif/Sans Serif, which should be an alias to deja-vu (default)

As soon as I either change fonts (tried with Arial) or disable font antialiasing I can't reproduce it anymore.

I will reproduce it for you tomorrow and add the output requested. Please note that in the meantime I updated the intel driver with the xorg-updates ppa, but the problem stays the same. Just as a sidenote, as the output will differ from what I wrote in the original report.

Thanks so far, kind regards

Christian

As promised I attached the information I was asked for.

Even though I am quite sure that it wont help much, as the interesting thing about Xorg is the Segmentation Fault with back trace.

As far as I can see/guess, there is some caching going on for glyphs when font antialiasing is enabled. However, some applications (kmail is easiest, maybe due to the fact that it hides windows?) seems to trigger a glyph lookup which tries to fetch from an invalid / forbidden memory section. This is why it's a bit hard for me to tell which package really causes this, but my best guess is Xorg and the video driver. I know that this is a bug which might be hard to reproduce, but unfortunately I can't do much more.

As said, this only happens with font antialiasing enabled, and only with some fonts (default binding for serif/sans serif, which should be dejavu). Easiest way to trigger: (might be better to do this in gnome) go to systemsettings, font settings, revert all settings to standard, apply, start kmail, reply to a mail. Xorg should crash. At least it does that here, 100% reproducible.

Kind regards,

Christian

This bug seems to affect me too, but not with xserver-xorg-video-intel but with nvidia's proprietary driver (185.18.36-0ubuntu8). Also, it is not as reliably reproducible for me, xorg just crashes more or less randomly. I am also using the default fonts (DejaVu) and anti-aliasing.

Why is this bug still marked as incomplete?

I delivered the requested information long time ago and got no feedback.
I don't see why it should expired due to this wrong status ...

If you need further information, please request it.

If I get no further feedback, I will change this status before the bug expires.

Kind regards,

Christian

Seems other people got this on different drivers as well,

http://lists.freedesktop.org/archives/xorg/2009-March/044396.html
http://bugs.gentoo.org/show_bug.cgi?id=288747

Even though the report is old, it seems to happen with recent versions of xorg as well.

Could you please check whether this patch has been applied with upstream, and if not, whether it would make sense to apply it?

Xorg crashing is a severe issue, as it takes down all applications (with unsaved documents) started in it as well.

Kind regards,

Christian

This issue was reported against karmic, so can you confirm if this issue exists with the most recent Lucid Lynx 10.04 Alpha release? ISO CD images are available at http://cdimage.ubuntu.com/releases/lucid/ . Thanks in advance.