Re: Bug#753816: [systemd] Broken audio
El 06/07/14 05:34, Ben Hutchings escribió: On Sat, 2014-07-05 at 18:58 +0200, Michael Biebl wrote: Am 05.07.2014 18:38, schrieb Antonio Marcos López Alonso: El 05/07/14 17:06, Michael Biebl escribió: Am 05.07.2014 17:56, schrieb Antonio Marcos López Alonso: Just in case, have you noticed I'm using an ALSA-Jack loopback setting for audio? Under sysvinit, udev (including udevadm settle) is started before the kmod init script, which loads snd_aloop. That means, snd_aloop is loaded after snd_hda_intel. Under systemd, it looks like the snd_aloop module is loaded about the same time systemd-udevd is started. There might be a race here and snd_aloop is loaded before snd_hda_intel. This *might* be the reason, but I'm no expert on this matter. Can you try removing snd_aloop from /etc/modules and test if that makes a difference. OK removed snd_aloop and audio is back. Then reloaded the module, restarted JACK and audio is still fine. So as you said there must be some race condition in there. Should I keep this ticket opened? Hm, not sure what to do about this. We could order systemd-load-modules.service after systemd-udevd.service. But that doesn't guarantee the loading order of the modules and it feels like papering over the underlying issue. I'm no sound expert, but I'd say that the loading order should not matter. Maybe we need some input from the kernel team or some alsa experts here. I think this is due to ALSA userland (or maybe higher levels) being stupid about device selection. I think the default is to use sound device 0, which can be whichever driver won the race. I took the liberty to CC the Debian kernel team and the maintainer of the snd_aloop module. I hope they can help us here. For reference the complete bug report is at [1] Michael [1] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=753816 I think the usual workaround is to add 'index=1' to the snd-aloop line in /etc/modules. It is probably possible to do something more sophisticated in an ALSA configuration file. Ben. Adding 'index=1' didn't work. I still have to reload snd_aloop and restart JACK to get audio back. Antonio -- To UNSUBSCRIBE, email to debian-kernel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org Archive: https://lists.debian.org/53b90b59.6040...@gmail.com
Re: Bug#753816: [systemd] Broken audio
Am 06.07.2014 10:39, schrieb Antonio Marcos López Alonso: El 06/07/14 05:34, Ben Hutchings escribió: I think the usual workaround is to add 'index=1' to the snd-aloop line in /etc/modules. It is probably possible to do something more sophisticated in an ALSA configuration file. Adding 'index=1' didn't work. I still have to reload snd_aloop and restart JACK to get audio back. Be aware that systemd-modules-load does *not* read module parameters from /etc/modules. You'll need to set them via a /etc/modprobe.d/ file. -- Why is it that all of the instruments seeking intelligent life in the universe are pointed away from Earth? signature.asc Description: OpenPGP digital signature
Re: Bug#753816: [systemd] Broken audio
Michael Biebl bi...@debian.org writes: Be aware that systemd-modules-load does *not* read module parameters from /etc/modules. You'll need to set them via a /etc/modprobe.d/ file. Hmm... Is that considered a bug, or is it just the way things are going to be? The modules(5) man page from the kmod package still says The /etc/modules file contains the names of kernel modules that are to be loaded at boot time, one per line. Arguments can be given in the same line as the module name. Lines beginning with a '#' are ignored. and I would expect a few might have used that feature in the past. It seems unnecessary to break such configurations. Bjørn -- To UNSUBSCRIBE, email to debian-kernel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org Archive: https://lists.debian.org/87oax2s3oq@nemi.mork.no
Re: Bug#753816: [systemd] Broken audio
El 06/07/14 12:59, Michael Biebl escribió: Am 06.07.2014 10:39, schrieb Antonio Marcos López Alonso: El 06/07/14 05:34, Ben Hutchings escribió: I think the usual workaround is to add 'index=1' to the snd-aloop line in /etc/modules. It is probably possible to do something more sophisticated in an ALSA configuration file. Adding 'index=1' didn't work. I still have to reload snd_aloop and restart JACK to get audio back. Be aware that systemd-modules-load does *not* read module parameters from /etc/modules. You'll need to set them via a /etc/modprobe.d/ file. Ah! It sounded somewhat strange but as this module stuff is a sort of terra incognita for me... :) Now I created a /etc/modprobe.d/snd-aloop.conf file which contains a single line with 'options snd-aloop index=1' and everything is fine again after boot! Thanks a lot for your tips! Antonio -- To UNSUBSCRIBE, email to debian-kernel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org Archive: https://lists.debian.org/53b9a5b1.10...@gmail.com
Re: Bug#753816: [systemd] Broken audio
Am 05.07.2014 18:38, schrieb Antonio Marcos López Alonso: El 05/07/14 17:06, Michael Biebl escribió: Am 05.07.2014 17:56, schrieb Antonio Marcos López Alonso: Just in case, have you noticed I'm using an ALSA-Jack loopback setting for audio? Under sysvinit, udev (including udevadm settle) is started before the kmod init script, which loads snd_aloop. That means, snd_aloop is loaded after snd_hda_intel. Under systemd, it looks like the snd_aloop module is loaded about the same time systemd-udevd is started. There might be a race here and snd_aloop is loaded before snd_hda_intel. This *might* be the reason, but I'm no expert on this matter. Can you try removing snd_aloop from /etc/modules and test if that makes a difference. OK removed snd_aloop and audio is back. Then reloaded the module, restarted JACK and audio is still fine. So as you said there must be some race condition in there. Should I keep this ticket opened? Hm, not sure what to do about this. We could order systemd-load-modules.service after systemd-udevd.service. But that doesn't guarantee the loading order of the modules and it feels like papering over the underlying issue. I'm no sound expert, but I'd say that the loading order should not matter. Maybe we need some input from the kernel team or some alsa experts here. I took the liberty to CC the Debian kernel team and the maintainer of the snd_aloop module. I hope they can help us here. For reference the complete bug report is at [1] Michael [1] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=753816 -- Why is it that all of the instruments seeking intelligent life in the universe are pointed away from Earth? signature.asc Description: OpenPGP digital signature
Re: Bug#753816: [systemd] Broken audio
On Sat, 2014-07-05 at 18:58 +0200, Michael Biebl wrote: Am 05.07.2014 18:38, schrieb Antonio Marcos López Alonso: El 05/07/14 17:06, Michael Biebl escribió: Am 05.07.2014 17:56, schrieb Antonio Marcos López Alonso: Just in case, have you noticed I'm using an ALSA-Jack loopback setting for audio? Under sysvinit, udev (including udevadm settle) is started before the kmod init script, which loads snd_aloop. That means, snd_aloop is loaded after snd_hda_intel. Under systemd, it looks like the snd_aloop module is loaded about the same time systemd-udevd is started. There might be a race here and snd_aloop is loaded before snd_hda_intel. This *might* be the reason, but I'm no expert on this matter. Can you try removing snd_aloop from /etc/modules and test if that makes a difference. OK removed snd_aloop and audio is back. Then reloaded the module, restarted JACK and audio is still fine. So as you said there must be some race condition in there. Should I keep this ticket opened? Hm, not sure what to do about this. We could order systemd-load-modules.service after systemd-udevd.service. But that doesn't guarantee the loading order of the modules and it feels like papering over the underlying issue. I'm no sound expert, but I'd say that the loading order should not matter. Maybe we need some input from the kernel team or some alsa experts here. I think this is due to ALSA userland (or maybe higher levels) being stupid about device selection. I think the default is to use sound device 0, which can be whichever driver won the race. I took the liberty to CC the Debian kernel team and the maintainer of the snd_aloop module. I hope they can help us here. For reference the complete bug report is at [1] Michael [1] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=753816 I think the usual workaround is to add 'index=1' to the snd-aloop line in /etc/modules. It is probably possible to do something more sophisticated in an ALSA configuration file. Ben. -- Ben Hutchings The most exhausting thing in life is being insincere. - Anne Morrow Lindberg signature.asc Description: This is a digitally signed message part
