[alsa-devel] [Re: Crash when snd_pcm_open is called from a thread with "pulse" as playback]
Hi folks,
I'd need the help of some alsa developpers regarding the bug report : https://bugtrack.alsa-project.org/alsa-bug/view.php?id=4426
We've made a few progress on it, but we are stuck again.
Basically, it seems that calling snd_config_update_free_global() from a pthread causes the program to crash when the thread terminates.
Questions are:
Should config_update_free_global NOT be called from a thread ?
In other words, is the following code valid (though dumb :=)) ? Or is there some reason for it to crash ?
********************************** #include <pthread.h> #include <alsa/asoundlib.h> void * threadWork(void *arg) { snd_pcm_t *playback_handle; if (snd_pcm_open (&playback_handle, "default", SND_PCM_STREAM_PLAYBACK, 0) < 0) fprintf (stderr, "error\n"; snd_pcm_close(playback_handle);
snd_config_update_free_global(); return NULL; } int main() { pthread_attr_t attr; pthread_attr_init(&attr); pthread_t threadid; pthread_create( &threadid, &attr, threadWork, NULL); return EXIT_SUCCESS; } **********************************
I thank you much,
Nicolas
---------------------------- Message original ---------------------------- Objet: Crash when snd_pcm_open is called from a thread with "pulse" as playback De: castagne@imag.fr Date: Mer 4 mars 2009 8:20 À: alsa-devel@alsa-project.org --------------------------------------------------------------------------
Hi folks,
I hope I post on the correct mail list... I've read somewhere that I should report bugs on a list, and not only on the Tracker. That's the aim of this message.
On all my Fedora 10 machines, whenever snd_pcm_open has been called from a pthread using "pulse" as playback then the program crashes when the thread terminates.
Crash in __nptl_deallocate_tsd
However, AFAIK, one should be able to call snd_pcm_open from a thread.
The full bug report is there, with a very simple sample code : https://bugtrack.alsa-project.org/alsa-bug/view.php?id=4426
I think this bug relates directly to alsa. I hope this report is useful.
Best- Nicolas
At Sun, 8 Mar 2009 16:11:45 -0000 (GMT), Nicolas.Castagne@imag.fr wrote:
Hi folks,
I'd need the help of some alsa developpers regarding the bug report : https://bugtrack.alsa-project.org/alsa-bug/view.php?id=4426
We've made a few progress on it, but we are stuck again.
Basically, it seems that calling snd_config_update_free_global() from a pthread causes the program to crash when the thread terminates.
Questions are:
Should config_update_free_global NOT be called from a thread ?
In other words, is the following code valid (though dumb :=)) ? Or is there some reason for it to crash ?
Hm, I don't see any reason, and I cannot reproduce a crash on my machine...
Takashi
#include <pthread.h> #include <alsa/asoundlib.h> void * threadWork(void *arg) { snd_pcm_t *playback_handle; if (snd_pcm_open (&playback_handle, "default", SND_PCM_STREAM_PLAYBACK, 0) < 0) fprintf (stderr, "error\n"; snd_pcm_close(playback_handle);
snd_config_update_free_global(); return NULL;} int main() { pthread_attr_t attr; pthread_attr_init(&attr); pthread_t threadid; pthread_create( &threadid, &attr, threadWork, NULL); return EXIT_SUCCESS; }
I thank you much,
Nicolas
---------------------------- Message original ---------------------------- Objet: Crash when snd_pcm_open is called from a thread with "pulse" as playback De: castagne@imag.fr Date: Mer 4 mars 2009 8:20 À: alsa-devel@alsa-project.org
Hi folks,
I hope I post on the correct mail list... I've read somewhere that I should report bugs on a list, and not only on the Tracker. That's the aim of this message.
On all my Fedora 10 machines, whenever snd_pcm_open has been called from a pthread using "pulse" as playback then the program crashes when the thread terminates.
Crash in __nptl_deallocate_tsd
However, AFAIK, one should be able to call snd_pcm_open from a thread.
The full bug report is there, with a very simple sample code : https://bugtrack.alsa-project.org/alsa-bug/view.php?id=4426
I think this bug relates directly to alsa. I hope this report is useful.
Best- Nicolas
Alsa-devel mailing list Alsa-devel@alsa-project.org http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
On Mon, 9 Mar 2009, Takashi Iwai wrote:
At Sun, 8 Mar 2009 16:11:45 -0000 (GMT), Nicolas.Castagne@imag.fr wrote:
Hi folks,
I'd need the help of some alsa developpers regarding the bug report : https://bugtrack.alsa-project.org/alsa-bug/view.php?id=4426
We've made a few progress on it, but we are stuck again.
Basically, it seems that calling snd_config_update_free_global() from a pthread causes the program to crash when the thread terminates.
Questions are:
Should config_update_free_global NOT be called from a thread ?
In other words, is the following code valid (though dumb :=)) ? Or is there some reason for it to crash ?
Hm, I don't see any reason, and I cannot reproduce a crash on my machine...
I would suggest to comment out code from snd_config_update_free_global(). Try to comment out snd_dlobj_cache_cleanup() at first. You may compile alsa-lib from the tar ball on www.alsa-project.org and use LD_PRELOAD=alsa-lib/src/.libs/libasound.so.2.0.0 <your_program> for tests.
Jaroslav
----- Jaroslav Kysela perex@perex.cz Linux Kernel Sound Maintainer ALSA Project, Red Hat, Inc.
Hi Jaroslav, Takashi and all,
thx for you answers.
Takashi :
Hm, I don't see any reason, and I cannot reproduce a crash on my machine...
I can reproduce it on my three Fedora10 machines, using 2 hardware.
Jaroslav
I would suggest to comment out code from snd_config_update_free_global(). Try to comment out snd_dlobj_cache_cleanup() at first. You may compile alsa-lib from the tar ball on www.alsa-project.org and use LD_PRELOAD=alsa-lib/src/.libs/libasound.so.2.0.0 <your_program> for tests.
Done.
* First, no more bug when commenting snd_dlobj_cache_cleanup
* Also, no more bug when commenting dlclose in snd_dlclose called from snd_dlobj_cache_cleanup
The only dynamically loaded lib is _snd_pcm_pulse_open
Seems once again that pulse is involved somewhere.
But dunno where to look at from this point :/
I upload these new inputs on the tracker.
Best- Nicolas
On Mon, 9 Mar 2009, Takashi Iwai wrote:
At Sun, 8 Mar 2009 16:11:45 -0000 (GMT), Nicolas.Castagne@imag.fr wrote:
Hi folks,
I'd need the help of some alsa developpers regarding the bug report : https://bugtrack.alsa-project.org/alsa-bug/view.php?id=4426
We've made a few progress on it, but we are stuck again.
Basically, it seems that calling snd_config_update_free_global() from
a
pthread causes the program to crash when the thread terminates.
Questions are:
Should config_update_free_global NOT be called from a thread ?
In other words, is the following code valid (though dumb :=)) ? Or is there some reason for it to crash ?
Hm, I don't see any reason, and I cannot reproduce a crash on my machine...
I would suggest to comment out code from snd_config_update_free_global(). Try to comment out snd_dlobj_cache_cleanup() at first. You may compile alsa-lib from the tar ball on www.alsa-project.org and use LD_PRELOAD=alsa-lib/src/.libs/libasound.so.2.0.0 <your_program> for tests.
Jaroslav
Jaroslav Kysela perex@perex.cz Linux Kernel Sound Maintainer ALSA Project, Red Hat, Inc.
Alsa-devel mailing list Alsa-devel@alsa-project.org http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
On Mon, 9 Mar 2009 Nicolas.Castagne@imag.fr wrote:
Hi Jaroslav, Takashi and all,
thx for you answers.
Takashi :
Hm, I don't see any reason, and I cannot reproduce a crash on my machine...
I can reproduce it on my three Fedora10 machines, using 2 hardware.
Jaroslav
I would suggest to comment out code from snd_config_update_free_global(). Try to comment out snd_dlobj_cache_cleanup() at first. You may compile alsa-lib from the tar ball on www.alsa-project.org and use LD_PRELOAD=alsa-lib/src/.libs/libasound.so.2.0.0 <your_program> for tests.
Done.
First, no more bug when commenting snd_dlobj_cache_cleanup
Also, no more bug when commenting dlclose in snd_dlclose called from snd_dlobj_cache_cleanup
The only dynamically loaded lib is _snd_pcm_pulse_open
Seems once again that pulse is involved somewhere.
Maybe. I guess it's a glibc bug which might be Fedora specific. Could you try glibc from different distribution (or maybe rawhide) using LD_PRELOAD hack if this bug can be reproduced? Just unpack glibc rpm with rpm2cpio and use libc.so, libdl.so and libphread.so files for LD_PRELOAD.
Jaroslav
----- Jaroslav Kysela perex@perex.cz Linux Kernel Sound Maintainer ALSA Project, Red Hat, Inc.
Hi Jaroslav & all,
Maybe. I guess it's a glibc bug which might be Fedora specific. Could you try glibc from different distribution (or maybe rawhide) using LD_PRELOAD hack if this bug can be reproduced? Just unpack glibc rpm with rpm2cpio and use libc.so, libdl.so and libphread.so files for LD_PRELOAD.
Well, these are manipulations I am not used to :( In particular, I never installed rawhide.
But I tried the pre compiled libraries in http://download.fedora.redhat.com then used the downloaded libc.so, libdl.so and libphread.so at run time.
-> Fedora development version glibc-2.9.90-8.1.i686.rpm Newer than mine. Found in : http://download.fedora.redhat.com/pub/fedora/linux/development/i386/os/Packa...
-> Fedora release version glibc-2.9-2.i686.rpm Older than mine. Found in : http://download.fedora.redhat.com/pub/fedora/linux/releases/10/Everything/i3...
The bug is still there with both these versions.
I've tried using another glibc (eg ubuntu), but I must say I have difficulties looking into them...
Perhaps someone has Fedora Rawhide installed, and could test ?
If this is possible he sample program is alsa_main.cpp, available at : https://bugtrack.alsa-project.org/alsa-bug/view.php?id=4426
Cheers, Nicolas
On Mon, 9 Mar 2009 Nicolas.Castagne@imag.fr wrote:
Hi Jaroslav, Takashi and all,
thx for you answers.
Takashi :
Hm, I don't see any reason, and I cannot reproduce a crash on my
machine...
I can reproduce it on my three Fedora10 machines, using 2 hardware.
Jaroslav
I would suggest to comment out code from
snd_config_update_free_global().
Try to comment out snd_dlobj_cache_cleanup() at first. You may compile alsa-lib from the tar ball on www.alsa-project.org and use LD_PRELOAD=alsa-lib/src/.libs/libasound.so.2.0.0 <your_program> for
tests.
Done.
First, no more bug when commenting snd_dlobj_cache_cleanup
Also, no more bug when commenting dlclose in snd_dlclose called from snd_dlobj_cache_cleanup
The only dynamically loaded lib is _snd_pcm_pulse_open
Seems once again that pulse is involved somewhere.
Maybe. I guess it's a glibc bug which might be Fedora specific. Could you try glibc from different distribution (or maybe rawhide) using LD_PRELOAD hack if this bug can be reproduced? Just unpack glibc rpm with rpm2cpio and use libc.so, libdl.so and libphread.so files for LD_PRELOAD.
Jaroslav
Jaroslav Kysela perex@perex.cz Linux Kernel Sound Maintainer ALSA Project, Red Hat, Inc.
Alsa-devel mailing list Alsa-devel@alsa-project.org http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
participants (3)
-
Jaroslav Kysela -
Nicolas.Castagne＠imag.fr -
Takashi Iwai