Arch Linux

dcecile

Member

From: Canada

Registered: 2011-08-08

Posts: 14

Website

[SOLVED] /dev/snd/* permissions problem

Another user had a udev permissions problem in the System broken after update thread, but my problem didn't go away after regenerating my /lib/udev/rules.d folder. (I tried "mv /lib/udev/rules.d /lib/udev/rules.d.old; pacman -S $(pacman -Ql | grep /lib/udev/rules.d | awk '{ print $1 }' | sort -u)".)

After the upgrade to Linux 3.0.7 and udev 174, my ALSA devices under /dev/snd have the wrong permissions:

drwxr-xr-x 2 root root       60 Oct 31 17:31 /dev/snd/by-path/
crw------- 1 root root  116,  5 Oct 31 17:31 /dev/snd/controlC0
crw------- 1 root root  116,  4 Oct 31 17:31 /dev/snd/hwC0D0
crw------- 1 root root  116,  3 Oct 31 17:31 /dev/snd/pcmC0D0c
crw------- 1 root root  116,  2 Oct 31 17:31 /dev/snd/pcmC0D0p
crw-rw---T 1 root audio 116,  1 Oct 31 17:31 /dev/snd/seq
crw------T 1 root root  116, 33 Oct 31 17:31 /dev/snd/timer

With these permissions, I can't start any ALSA applications without doing a "sudo chown" hack first.

After downgrading Linux and udev (and mkinitcpio and filesystem), the permissions are back to normal, and ALSA applications have no problems:

drwxr-xr-x 2 root root       60 Oct 31 18:13 /dev/snd/by-path/
crw-rw---- 1 root audio 116,  5 Oct 31 18:13 /dev/snd/controlC0
crw-rw---- 1 root audio 116,  4 Oct 31 18:13 /dev/snd/hwC0D0
crw-rw---- 1 root audio 116,  3 Oct 31 18:13 /dev/snd/pcmC0D0c
crw-rw---- 1 root audio 116,  2 Oct 31 18:13 /dev/snd/pcmC0D0p
crw-rw---- 1 root audio 116,  1 Oct 31 18:13 /dev/snd/seq
crw-rw---- 1 root audio 116, 33 Oct 31 18:13 /dev/snd/timer

Last edited by dcecile (2011-11-19 12:17:21)

dcecile

Member

From: Canada

Registered: 2011-08-08

Posts: 14

Website

Re: [SOLVED] /dev/snd/* permissions problem

After upgrading to udev 175-1 and Linux 3.1.1-1, things are working fine.

Here's the new permissions for my /dev/snd files:

crw-rw---T 1 root audio 116,  5 Nov 19 07:15 /dev/snd/controlC0
crw-rw---T 1 root audio 116,  4 Nov 19 07:15 /dev/snd/hwC0D0
crw-rw---T 1 root audio 116,  3 Nov 19 07:15 /dev/snd/pcmC0D0c
crw-rw---T 1 root audio 116,  2 Nov 19 07:15 /dev/snd/pcmC0D0p
crw-rw---T 1 root audio 116,  1 Nov 19 07:15 /dev/snd/seq
crw-rw---T 1 root audio 116, 33 Nov 19 07:15 /dev/snd/timer