Unstable desktop experience with kernel > 2.6.38

[Émeric Maschino <emeric.maschino@gmail.com>]

Hi,

Since there's a workaround allowing us to go kernel > 2.6.38
(http://lists.debian.org/debian-ia64/2012/01/msg00013.html), I
obviously updated my Testing system to current
linux-image-3.1.0-1-mckinley_3.1.8-2_ia64.deb.

Well, graphical desktop experience is _unstable_. When I say "desktop
experience", I'm talking about basic desktop tasks, not fancy OpenGL
rendering. I have at least two reproducible scenari (I'm running Gnome
Classic):
- random X restart while typing into a GNOME terminal window
- Iceweasel killed when I try to click on the Back button or while
trying to click on the Edit menu.

For the latter one, I managed to get a stack trace with gdb, before
gdb itself core dumped (huge core available if interested!) or X is
restarted... It seems that something goes wrong with PulseAudio when
running kernel 3.1:

Program received signal SIGABRT, Aborted.
[Switching to Thread 0x7002b5231e0 (LWP 2282)]
0xa000000000040721 in __kernel_syscall_via_break ()

Thread 19 (Thread 0x7002b5231e0 (LWP 2282)):
#0  0xa000000000040721 in __kernel_syscall_via_break ()
No symbol table info available.
#1  0x200000000031a900 in raise () from /lib/ia64-linux-gnu/libc.so.6.1
No symbol table info available.
#2  0x2000000000322eb0 in abort () from /lib/ia64-linux-gnu/libc.so.6.1
No symbol table info available.
#3  0x000007001612a310 in pa_mutex_unlock ()
   from /usr/lib/ia64-linux-gnu/libpulsecommon-1.0.so
No symbol table info available.
#4  0x000007001604f8b0 in poll_func ()
   from /usr/lib/ia64-linux-gnu/libpulse.so.0
No symbol table info available.

Rebooting my Testing system with good old kernel 2.6.38-5 brings a
stable desktop experience back.

I've performed regression testing: the issue is already there with
linux-image-2.6.39-rc4-mckinley_2.6.39~rc4-1~experimental.1_ia64.deb,
the immediate successor to
linux-image-2.6.38-2-mckinley_2.6.38-5_ia64.deb in
snapshot.debian.org. Latest available
linux-image-3.2.0-rc7-mckinley_3.2~rc7-1~experimental.1_ia64.deb still
provides unstable desktop experience.

Does this sound familiar to someone? Is this problem already known and
reported somewhere or is it worth filing a bug and going the git
bisect route?

     Émeric