Bug#384505: libgl1-mesa-glx: segfaults in multithreaded apps (fixed upstream)

[Jan Gukelberger]

Package: libgl1-mesa-glx
Version: 6.4.2-1.1
Severity: normal

Calling gl-functions from a thread other than the program's main thread
causes reproducible segfaults.

Example backtrace:
---------------------------------------------------------------------
#0  0xa79cdbef in _mesa_LoadIdentity () from /usr/lib/dri/r200_dri.so
#1  0xa7f5ac64 in glLoadIdentity () from /usr/lib/libGL.so.1
#2  0x0804ac85 in thread_loop () at GlxSyncTest.cpp:554
#3  0xa7eaa260 in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
#4  0xa7d2529e in clone () from /lib/tls/i686/cmov/libc.so.6
---------------------------------------------------------------------

I've observed the very same behaviour on a Radeon (r200) and a Matrox
(mga) machine. A small example program code could be provided if it was of
help.

However, upgrading to the head of the mesa_6_4_branch in mesa cvs fixes
the bug for me. I presume the relevant commits are the following:

---------------------------------------------------------------------
Wed Mar 15 20:46:09 2006 UTC (5 months, 1 week ago) by brianp 
Branch: mesa_6_4_branch 
remove invalid assertion in _glapi_get_dispatch(), fixes additional
thread safety problem
---------------------------------------------------------------------
Wed Mar 15 20:32:48 2006 UTC (5 months, 1 week ago) by brianp
Branch: mesa_6_4_branch 
thread safety fix from trunk
---------------------------------------------------------------------

How about incorporating the changes from the mesa_6_4_branch into the
debian package? There shouldn't be too disruptive changes in this
bugfix-only branch.

-- System Information:
Debian Release: testing/unstable
  APT prefers testing
  APT policy: (990, 'testing'), (500, 'unstable')
Architecture: i386 (i686)
Shell:  /bin/sh linked to /bin/bash
Kernel: Linux 2.6.16preempt
Locale: LANG=C, LC_CTYPE=C (charmap=ANSI_X3.4-1968)

Versions of packages libgl1-mesa-glx depends on:
ii  libc6                         2.3.6-15   GNU C Library: Shared libraries
ii  libdrm2                       2.0.1-1    Userspace interface to kernel DRM 
ii  libx11-6                      2:1.0.0-8  X11 client-side library
ii  libxext6                      1:1.0.0-4  X11 miscellaneous extension librar
ii  libxxf86vm1                   1:1.0.0-4  X11 XFree86 video mode extension l

libgl1-mesa-glx recommends no packages.

-- no debconf information