ubuntu-x-swat team mailing list archive

[TJ <ubuntu@xxxxxxxxxxx>]

Public bug reported:

In trying to debug the Lucid xserver crash-on-first-session-start
issues. I have installed "xserver-xorg-dbgsym" in the hope that the
backtrace of "/usr/bin/X" would reveal more detail via a core dump
instead of the "Xorg.0.log" report:

-----
Backtrace:
0: /usr/bin/X (xorg_backtrace+0x3b) [0x80e880b]
1: /usr/bin/X (0x8048000+0x61aed) [0x80a9aed]
2: (vdso) (__kernel_rt_sigreturn+0x0) [0xc06410]
3: /usr/bin/X (0x8048000+0x2a190) [0x8072190]
4: /usr/bin/X (0x8048000+0x1ed3a) [0x8066d3a]
5: /lib/tls/i686/cmov/libc.so.6 (__libc_start_main+0xe6) [0x25fbd6]
6: /usr/bin/X (0x8048000+0x1e921) [0x8066921]

Caught signal 3 (Quit). Server aborting
-----

I added the NoTrapSignals option to xorg.conf as detailed at

 https://wiki.ubuntu.com/DebuggingProgramCrash#The%20Xorg%20server

----- /etc/X11/xorg.conf fragment -----
Section "ServerFlags"
        Option "NoTrapSignals" "true"
EndSection
-----

But on restarting the PC and encountering the bug the signal is still
caught by the xserver. The xorg.0.log shows the option is recognised:

-----
...
(==) Using config file: "/etc/X11/xorg.conf"
(==) ServerLayout "Default Layout"
(**) |-->Screen "Default Screen" (0)
(**) |   |-->Monitor "LCD Panel 1024x768"
(**) |   |-->Device "Intel Corporation 82815 CGC"
(**) Option "NoTrapSignals" "true"
...
Backtrace:
0: /usr/bin/X (xorg_backtrace+0x3b) [0x80e880b]
1: /usr/bin/X (0x8048000+0x61aed) [0x80a9aed]
2: (vdso) (__kernel_rt_sigreturn+0x0) [0xc06410]
3: /usr/bin/X (0x8048000+0x2a190) [0x8072190]
4: /usr/bin/X (0x8048000+0x1ed3a) [0x8066d3a]
5: /lib/tls/i686/cmov/libc.so.6 (__libc_start_main+0xe6) [0x25fbd6]
6: /usr/bin/X (0x8048000+0x1e921) [0x8066921]

Caught signal 3 (Quit). Server aborting
-----

The debug symbols are installed:

ls -l /usr/lib/debug/usr/bin/
ls -l /usr/lib/debug/usr/bin/
total 6404
-rw-r--r-- 1 root root   17289 2010-03-02 17:00 cvt
-rw-r--r-- 1 root root   11387 2010-03-02 17:00 gtf
-rwxr-xr-x 1 root root   10911 2010-03-04 04:13 X
-rw-r--r-- 1 root root 6510542 2010-03-02 17:00 Xorg

** Affects: xorg-server (Ubuntu)
     Importance: Undecided
         Status: New

-- 
[Lucid] Option NoTrapSignals ignored when debugging xserver
https://bugs.launchpad.net/bugs/532845
You received this bug notification because you are a member of Ubuntu-X,
which is subscribed to xorg-server in ubuntu.