On Mon, Jan 23, 2012 at 10:51:43AM +0100, Takashi Iwai wrote:
At Mon, 23 Jan 2012 10:46:30 +0100, Petr Baudis wrote:
On Mon, Jan 23, 2012 at 10:18:24AM +0100, Takashi Iwai wrote:
Thanks. Switching to the polling mode is really harmless. So, basically you can ignore these messages. I can change it only as a debug message.
OTOH, if the switching to single_cmd mode happens, this is a serious problem. But, as far as I see in alsa-info.sh output, it didn't happen.
Ok, then the bug is in handling of polling mode in this particular chip. After such switch to polling mode, applications will get stuck on releasing the soundcard.
What do you mean "releasing the soundcard"? Closing the PCM stream, or unloading the module, or at shutdown?
Closing the PCM stream - see strace snippet in the original post.
Another symptom I forgot to describe is that the last ~100ms of output will keep repeating when I pause/stop playback, one has to mute the volume to get rid of this. Again, this starts happenning only sometimes after the switch to polling mode, but then keeps happenning fairly consistently.
Hm, this sounds like some interrupt issue, then. After all, switching to the polling-mode happens because the expected interrupt didn't arrive in time. If a similar problem happens in the PCM stream, too, it might be some other generic interrupt problem.
The soundcard used to work on much older kernel versions. The only issue I had with this chipset were general (sound, network, ...) DMA problems from 4GiB+ memory areas after I upgraded my memory, but that got fixed in newer kernel version. The soundcard uses unique IRQs:
CPU0 CPU1 43: 24 7290 PCI-MSI-edge snd_hda_intel 44: 1 60 PCI-MSI-edge snd_hda_intel
Any clues on how I can debug this?