ALSA / aRTS Permissions Issues

[timpalpant]

Well, I've tried for about a week and can't seem to figure out this permissions deal with my soundcard, so I figured it's time to turn to the forums.

My soundcard has worked fine ever since I started using Sabayon, but some update about a week ago messed up the permissions (?) or something on the device so I can't get anything to work.

When I login to KDE, there is a message that reads:

Code: Select all

Sound server informational message:
Error while initializing the sound driver:
device: /dev/dsp can't be opened for playback (Permission denied)
The sound server will continue, using the null output device.

As a result, no audio works (duh), KMix reports that there are no mixers, etc., etc. I've run alsaconf several times, and it detects my card and apparently sets it up (the module does get loaded), but I can't use it. I recompiled all aRTS and ALSA packages, made sure my user was added to the "audio" group, and even recompiled kernels 2.6.21 and 2.6.22 to make sure there were no issues, but no luck.

Any ideas how I could get this to work again? (udev, arts, alsa, ...)[/quote]

[dyingmuppet]

* What soundcard do you have and what package did you update?
* are you sure that you didn't remove sound support when recompiling the kernel?
* have you tried to reinstall alsa? usually alsa drivers are builtin the sabayon kernel, so you have to deactivate ALSA and OSS in the kernel but keep sound support activated, recompile the kernel and emerge alsa-driver.
!!Don't forget to update portage before doing an emerge...!!

The most common I suspect is that you deactivated alsa somewhere or uninstalled it so it can't find the drivers anymore. BTW are you sure you have set the soundservice in the KDE-configurationscreen to auto or alsa??


Grtzz DM

[timpalpant]

No, I'm sure alsa and sound support is still enabled, and I've tried multiple selections of the KDE Sound System.

Actually, I've figured out what the problem is, I just don't know how to fix it yet. My sound devices (/dev/sound/* for OSS, /dev/snd/* for ALSA) are created with the permissions 600-root:root. They should be 660-root:audio (so that users in the audio group can use the sound, i.e. me). I can manually set these permissions and restart aRTS, but the devices are recreated every time I boot.

So...I guess does anybody know what creates these /dev/sound/* and /dev/snd/* devices (I think it's udev (?)) and where I could configure the setup permissions for them ?

[dyingmuppet]

hmmm... tipical, I think this should be automatically set right and work.
have you tried reinstalling alsa packages? and are your config files updated? "# etc-update"
maybe you forgot this after updating the last time??

I'm not sure if this works, maybe somebody else has an answer

Grtzz DM

[mebitek]

take a look at this file /etc/udev/rules.d/50-udev.rules

here u must change ur owner group for alsa device...
to do that take a look here: http://reactivated.net/writing_udev_rules.html#syntax

hope it works....
zalut
mebitek

[timpalpant]

Mebitek, I definitely think that is the right track, I just can't understand why it isn't working as it (seems) it should. Here is the relevent portion of /etc/udev/rules.d/50-udev.rules:

Code: Select all

# alsa devices
SUBSYSTEM=="sound", GROUP="audio"
KERNEL=="controlC[0-9]*",   NAME="snd/%k", GROUP="audio", MODE="0660"
KERNEL=="hw[CD0-9]*",      NAME="snd/%k", GROUP="audio", MODE="0660"
KERNEL=="pcm[CD0-9cp]*",   NAME="snd/%k", GROUP="audio", MODE="0660"
KERNEL=="midiC[D0-9]*",      NAME="snd/%k", GROUP="audio", MODE="0660"
KERNEL=="timer",      NAME="snd/%k", GROUP="audio", MODE="0660"
KERNEL=="seq",         NAME="snd/%k", GROUP="audio", MODE="0660"

# sound devices
KERNEL=="adsp",         NAME="sound/%k", SYMLINK+="%k", GROUP="audio", MODE="0660"
KERNEL=="adsp[0-9]*",      NAME="sound/%k", SYMLINK+="%k", GROUP="audio", MODE="0660"
KERNEL=="audio",      NAME="sound/%k", SYMLINK+="%k", GROUP="audio", MODE="0660"
KERNEL=="audio[0-9]*",      NAME="sound/%k", SYMLINK+="%k", GROUP="audio", MODE="0660"
KERNEL=="dsp",         NAME="sound/%k", SYMLINK+="%k", GROUP="audio", MODE="0660"
KERNEL=="dsp[0-9]*",      NAME="sound/%k", SYMLINK+="%k", GROUP="audio", MODE="0660"
KERNEL=="mixer",      NAME="sound/%k", SYMLINK+="%k", GROUP="audio", MODE="0660"
KERNEL=="mixer[0-9]*",      NAME="sound/%k", SYMLINK+="%k", GROUP="audio", MODE="0660"
KERNEL=="sequencer",      NAME="sound/%k", SYMLINK+="%k", GROUP="audio", MODE="0660"
KERNEL=="sequencer[0-9]*",   NAME="sound/%k", SYMLINK+="%k", GROUP="audio", MODE="0660"

/etc/udev/permissions.d/50-udev.permissions:

Code: Select all

# audio devices
dsp*:root:audio:0660
audio*:root:audio:0660
midi*:root:audio:0660
mixer*:root:audio:0660
sequencer*:root:audio:0660
sound/*:root:audio:0660
snd/*:root:audio:0660
beep:root:audio:0660
admm*:root:audio:0660
adsp*:root:audio:0660
aload*:root:audio:0660
amidi*:root:audio:0660
dmfm*:root:audio:0660
dmmidi*:root:audio:0660
sndstat:root:audio:0660

actual permissions when I boot up:

Code: Select all

timlaptop ~ # cd /dev/snd/
timlaptop snd # ls -l
total 0
crw------- 1 root root  116,  0 2007-07-16 07:32 controlC0
crw------- 1 root root  116, 24 2007-07-16 07:32 pcmC0D0c
crw------- 1 root root  116, 16 2007-07-16 07:32 pcmC0D0p
crw------- 1 root root  116, 26 2007-07-16 07:32 pcmC0D2c
crw-rw---- 1 root audio 116,  1 2007-07-16 11:32 seq
crw------- 1 root root  116, 33 2007-07-16 07:32 timer
timlaptop snd # cd /dev/sound/
timlaptop sound # ls -l
total 0
crw------- 1 root root  14, 4 2007-07-16 07:32 audio
crw------- 1 root root  14, 3 2007-07-16 07:32 dsp
crw------- 1 root root  14, 0 2007-07-16 07:32 mixer
crw-rw---- 1 root audio 14, 1 2007-07-16 11:32 sequencer
crw-rw---- 1 root audio 14, 8 2007-07-16 11:32 sequencer2

I don't get it! Anyone have any ideas why this could be happening? All my configuration files are up-to-date, but I think something must be messed up somewhere (even though I've re-compiled udev, alsa, arts, and the kernel, multiple times). There has to be a more systematic way of figuring this out.

[mebitek]

it's strange...
but if this could help my /etc/udev/rules.d/50-udev.rules differs from the yours:

# alsa devices
SUBSYSTEM=="sound", GROUP="audio"
KERNEL=="controlC[0-9]*", NAME="snd/%k"
KERNEL=="hw[CD0-9]*", NAME="snd/%k"
KERNEL=="pcm[CD0-9cp]*", NAME="snd/%k"
KERNEL=="midiC[D0-9]*", NAME="snd/%k"
KERNEL=="timer", NAME="snd/%k"
KERNEL=="seq", NAME="snd/%k"

# sound devices
KERNEL=="adsp", NAME="sound/%k", SYMLINK+="%k", GROUP="audio"
KERNEL=="adsp[0-9]*", NAME="sound/%k", SYMLINK+="%k", GROUP="audio"
KERNEL=="audio", NAME="sound/%k", SYMLINK+="%k", GROUP="audio"
KERNEL=="audio[0-9]*", NAME="sound/%k", SYMLINK+="%k", GROUP="audio"
KERNEL=="dsp", NAME="sound/%k", SYMLINK+="%k", GROUP="audio"
KERNEL=="dsp[0-9]*", NAME="sound/%k", SYMLINK+="%k", GROUP="audio"
KERNEL=="mixer", NAME="sound/%k", SYMLINK+="%k", GROUP="audio"
KERNEL=="mixer[0-9]*", NAME="sound/%k", SYMLINK+="%k", GROUP="audio"

zalut
mebitek
KERNEL=="sequencer", NAME="sound/%k", SYMLINK+="%k", GROUP="audio"
KERNEL=="sequencer[0-9]*", NAME="sound/%k", SYMLINK+="%k", GROUP="audio"

[timpalpant]

I basically gave up because it makes no sense whatsoever. I tried re-merging all related packages several times, as well as using your config settings (pretty much the default, I think). I have no clue why the permissions are wrong.

To fix it I just added a manual chmod/chown statement to the end of the local.start init script, which solves the symptoms, even if we don't know why there's a problem.

Thanks for your ideas and help, I'm just gonna let this one go.

[Raqua]

I am having exactly the same problem.
Anyone solved it yet?

[Raqua]

I did some research and these packages look suspicious:
(I upgraded those recently)

1185666364: ::: completed emerge (1 of 11) sys-auth/pam_console-0.99.7.0.2.7-r1 to /
1185666604: ::: completed emerge (2 of 11) sys-auth/pam_userdb-0.99.8.1 to /
1185667068: ::: completed emerge (3 of 11) sys-libs/pam-0.99.8.1 to /

I have read somewhere that pam modifies permissions sometimes. Butt I have not found the solution yet. Anyone can point me in the right direction for in pam configs ?