On Sun, 2016-05-22 at 02:05 +0500, Alexander E. Patrakov wrote: > 22.05.2016 02:03, Alexander E. Patrakov wrote: > > > > If a card has been hot-plugged after pulseaudio start, alsa-lib still has > > old configuration in memory, which doesn't have PCM definitions for the > > new card. Thus, this error appears, and the device doesn't work: > > > > I: [pulseaudio] (alsa-lib)confmisc.c: Unable to find definition 'cards.USB-Audio.pcm.front.0:CARD=0' > > I: [pulseaudio] (alsa-lib)conf.c: function snd_func_refer returned error: No such file or directory > > I: [pulseaudio] (alsa-lib)conf.c: Evaluate error: No such file or directory > > I: [pulseaudio] (alsa-lib)pcm.c: Unknown PCM front:0 > > I: [pulseaudio] alsa-util.c: Error opening PCM device front:0: No such file or directory > > > > The snd_config_update_free_global() function makes alsa-lib forget any > > cached configuration and reparse all PCM definitions from scratch next > > time it is told to open anything. > > > > The trick has been copied from Phonon. > > > > Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=54029 > > Signed-off-by: Alexander E. Patrakov <patrakov at gmail.com> Thanks for the patch! > Obviously, the proposed patch is invalid if PulseAudio calls > snd_something_open() from more than one thread. I don't know if this is > the case. Technically PulseAudio does call snd_something_open() from multiple threads, but that's ok, because the only non-main thread calls are done when unsuspending, and unsuspending is done in the PA_SINK_MESSAGE_SET_STATE handler, which is processed synchronously. So the main thread is waiting while the IO thread does the unsuspending. I applied the patch to the "next" branch. -- Tanu
