Red Hat Bugzilla – Bug 447039
Kernel oops related to pcsp for 2.6.26-0.13.rc2.git5
Last modified: 2008-06-05 19:46:07 EDT
Description of problem:
After upgrading to kernel 2.6.26-0.13.rc2.git5.fc10.x86_64, system
sounds are gone. Instead, one can hear corresponding clicks emanating
from the PC speaker. dmesg reveals a backtrace which appears to be
related to this issue.
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. Upgrade to kernel-2.6.26-0.13.rc2.git5.fc10.x86_64
2. Reboot system.
3. Start GNOME session.
Click sounds from the PC speaker accompany system events.
GNOME sounds are played by the sound system.
- gnome-volume-control shows that the current audio device is pcsp.
- PulseAudio version is 0.9.10-1.fc9.
- ALSA version is 1.0.16-3.fc10.
Created attachment 305797 [details]
dmesg-2.6.26-0.13.rc2.git5.fc10.x86_64.txt with backtrace
Sound works again correctly with kernel-220.127.116.11-23.fc9.x86_64.
hmm, probably the addition of an ALSA driver for the PC speaker. This seems kind
of pointless, so I'll just turn it off.
Please check again with a build equal to or higher than
2.6.26-0.14.rc2.git5.fc10 when that appears.
PC speaker support actually sounds nice. Shouldn't this issue be dealt
with upstream then? I don't mind opening a new bug report over there.
Is this really useful ? From the Kconfig..
If you don't have a sound card in your computer, you can include a
driver for the PC speaker which allows it to act like a primitive
It's hard to imagine a machine without a sound card these days, given they
typically come onboard. Hmm, though I suppose it's useful if you have a speaker
in your PC, and no external speakers. The one concern I have is that adding
this driver will mean that everyone typically gets two ALSA output sources, and
which one gets picked by default is probably down to which driver gets loaded
first. For a lot of people, that would be annoying if suddenly their music
comes out of their PC instead of their speakers. Adding Lennart to the Cc,
perhaps he has some ideas on how to avoid that situation.
Another annoyance, is that this driver is unlikely to work well during some
periods of fedora development due to this..
/* Well, CONFIG_DEBUG_PAGEALLOC makes the sound horrible. Lets alert */
printk(KERN_WARNING "PCSP: CONFIG_DEBUG_PAGEALLOC is enabled, "
"which may make the sound noisy.\n");
(We enable that option from time to time, though the build you tried didn't have
it turned back on yet).
I'll forward the backtrace upstream.
Bug filed upstream at http://bugzilla.kernel.org/show_bug.cgi?id=10701
Both audio devices register correctly on my system:
card0/ cards devices oss/ pcsp@ timers
card1/ CK804@ modules pcm seq/ version
It is furthermore possible to choose the default device by means of
gnome-sound-properties. So far, so good. It is definitely worthwile
to have some simple audio capability in case no external speakers
are available. Notebooks are of cause exempted herefrom, but in
general, this appears to be a compelling feature.
The clicks that I have describe seem to be due to some deficiency of
the NForce chipset of my Tyan K8E mainboard. In general, you expect
at least system sounds to be reproduced in a reasonable manner.
Upstream bug is closed as CODE_FIX.