ALSA restore udev rule not working

[lopsided98]

Issue description

The udev rule that is supposed to restore ALSA state from /var/lib/alsa/asound.state does not seem to be working.

alsa-store.service correctly saves the ALSA state to asound.state, but it is not restored on boot. Running udevadm test /sys/devices/pci0000:00/0000:00:1b.0/sound/card0/controlC0 gives this output:

calling: test
version 239
This program is for debugging only, it does not run any program
specified by a RUN key. It may show incorrect results, because
some values may be different, or not available at a simulation run.

Load module index
Created link configuration context.
Reading rules file: /nix/store/0p6zrmkfnnq1c0yx7xfymlwsqjsl7h6d-udev-rules/00-path.rules
Reading rules file: /nix/store/0p6zrmkfnnq1c0yx7xfymlwsqjsl7h6d-udev-rules/01-md-raid-creating.rules
Reading rules file: /nix/store/0p6zrmkfnnq1c0yx7xfymlwsqjsl7h6d-udev-rules/10-dm.rules
Reading rules file: /nix/store/0p6zrmkfnnq1c0yx7xfymlwsqjsl7h6d-udev-rules/11-dm-lvm.rules
Reading rules file: /nix/store/0p6zrmkfnnq1c0yx7xfymlwsqjsl7h6d-udev-rules/13-dm-disk.rules
Reading rules file: /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/50-udev-default.rules
Reading rules file: /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/60-block.rules
Reading rules file: /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/60-cdrom_id.rules
Reading rules file: /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/60-drm.rules
Reading rules file: /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/60-evdev.rules
Reading rules file: /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/60-input-id.rules
Reading rules file: /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/60-persistent-alsa.rules
Reading rules file: /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/60-persistent-input.rules
Reading rules file: /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/60-persistent-storage-tape.rules
Reading rules file: /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/60-persistent-storage.rules
Reading rules file: /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/60-persistent-v4l.rules
Reading rules file: /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/60-sensor.rules
Reading rules file: /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/60-serial.rules
Reading rules file: /nix/store/0p6zrmkfnnq1c0yx7xfymlwsqjsl7h6d-udev-rules/60-zvol.rules
Reading rules file: /nix/store/0p6zrmkfnnq1c0yx7xfymlwsqjsl7h6d-udev-rules/63-md-raid-arrays.rules
Reading rules file: /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/64-btrfs.rules
Reading rules file: /nix/store/0p6zrmkfnnq1c0yx7xfymlwsqjsl7h6d-udev-rules/64-md-raid-assembly.rules
Reading rules file: /nix/store/0p6zrmkfnnq1c0yx7xfymlwsqjsl7h6d-udev-rules/69-bcache.rules
Reading rules file: /nix/store/0p6zrmkfnnq1c0yx7xfymlwsqjsl7h6d-udev-rules/69-md-clustered-confirm-device.rules
Reading rules file: /nix/store/0p6zrmkfnnq1c0yx7xfymlwsqjsl7h6d-udev-rules/69-vdev.rules
Reading rules file: /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/70-joystick.rules
Reading rules file: /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/70-mouse.rules
Reading rules file: /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/70-power-switch.rules
Reading rules file: /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/70-touchpad.rules
Reading rules file: /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/70-uaccess.rules
Reading rules file: /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/71-seat.rules
Reading rules file: /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/73-seat-late.rules
Reading rules file: /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/75-net-description.rules
Reading rules file: /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/75-probe_mtd.rules
Reading rules file: /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/78-sound-card.rules
Reading rules file: /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/80-drivers.rules
Reading rules file: /nix/store/0p6zrmkfnnq1c0yx7xfymlwsqjsl7h6d-udev-rules/80-net-setup-link.rules
Reading rules file: /nix/store/0p6zrmkfnnq1c0yx7xfymlwsqjsl7h6d-udev-rules/80-udisks2.rules
Reading rules file: /nix/store/0p6zrmkfnnq1c0yx7xfymlwsqjsl7h6d-udev-rules/89-alsa-ucm.rules
Reading rules file: /nix/store/0p6zrmkfnnq1c0yx7xfymlwsqjsl7h6d-udev-rules/90-alsa-restore.rules
Reading rules file: /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/90-vconsole.rules
Reading rules file: /nix/store/0p6zrmkfnnq1c0yx7xfymlwsqjsl7h6d-udev-rules/90-zfs.rules
Reading rules file: /nix/store/0p6zrmkfnnq1c0yx7xfymlwsqjsl7h6d-udev-rules/95-dm-notify.rules
Reading rules file: /nix/store/0p6zrmkfnnq1c0yx7xfymlwsqjsl7h6d-udev-rules/99-local.rules
Reading rules file: /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/99-systemd.rules
rules contain 49152 bytes tokens (4096 * 12 bytes), 19552 bytes strings
2356 strings (35022 bytes), 1600 de-duplicated (16227 bytes), 757 trie nodes used
GROUP 17 /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/50-udev-default.rules:43
IMPORT builtin 'path_id' /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/60-persistent-alsa.rules:11
LINK 'snd/by-path/pci-0000:00:1b.0' /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/60-persistent-alsa.rules:12
RUN 'uaccess' /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/73-seat-late.rules:17
ATTR '/sys/devices/pci0000:00/0000:00:1b.0/sound/card0/controlC0/../uevent' writing 'change' /nix/store/i2kkikrn30mfcm7v84cb840dnc4bm50c-systemd-239/lib/udev/rules.d/78-sound-card.rules:5
RUN '/nix/store/nc2970g9gzhfiz2v6z10i7jbmbib7qy1-alsa-utils-1.1.7/sbin/alsactl restore $attr{device/number}' /nix/store/0p6zrmkfnnq1c0yx7xfymlwsqjsl7h6d-udev-rules/90-alsa-restore.rules:5
handling device node '/dev/snd/controlC0', devnum=c116:6, mode=0660, uid=0, gid=17
preserve permissions /dev/snd/controlC0, 020660, uid=0, gid=17
preserve already existing symlink '/dev/char/116:6' to '../snd/controlC0'
found 'c116:6' claiming '/run/udev/links/\x2fsnd\x2fby-path\x2fpci-0000:00:1b.0'
creating link '/dev/snd/by-path/pci-0000:00:1b.0' to '/dev/snd/controlC0'
preserve already existing symlink '/dev/snd/by-path/pci-0000:00:1b.0' to '../controlC0'
ACTION=add
DEVLINKS=/dev/snd/by-path/pci-0000:00:1b.0
DEVNAME=/dev/snd/controlC0
DEVPATH=/devices/pci0000:00/0000:00:1b.0/sound/card0/controlC0
ID_PATH=pci-0000:00:1b.0
ID_PATH_TAG=pci-0000_00_1b_0
MAJOR=116
MINOR=6
PATH=/nix/store/1spfmb1dgfl1216bi442kh1fnp153vsf-udev-path/bin:/nix/store/1spfmb1dgfl1216bi442kh1fnp153vsf-udev-path/sbin
SUBSYSTEM=sound
TAGS=:uaccess:
USEC_INITIALIZED=65985748
run: 'uaccess'
run: '/nix/store/nc2970g9gzhfiz2v6z10i7jbmbib7qy1-alsa-utils-1.1.7/sbin/alsactl restore 0'
Unload module index
Unloaded link configuration context.

Manually running /nix/store/nc2970g9gzhfiz2v6z10i7jbmbib7qy1-alsa-utils-1.1.7/sbin/alsactl restore 0 correctly restores the state.

Steps to reproduce

1. Change mixer volumes
2. Reboot
3. Observe that volumes are not preserved

Technical details

• system: "x86_64-linux"
• host os: Linux 4.19.12, NixOS, 19.03pre164475.9ad20275d44-localpkgs (Koi)
• multi-user?: yes
• sandbox: yes
• version: nix-env (Nix) 2.1.3
• channels(ben): ""
• channels(root): "machines.HP-Z420.channel"
• nixpkgs: /nix/var/nix/profiles/per-user/root/channels/machines.HP-Z420.channel/nixpkgs

[stale[bot]]

Thank you for your contributions.

This has been automatically marked as stale because it has had no activity for 180 days.

If this is still important to you, we ask that you leave a comment below. Your comment can be as simple as "still important to me". This lets people see that at least one person still cares about this. Someone will have to do this at most twice a year if there is no other activity.

Here are suggestions that might help resolve this more quickly:

1. Search for maintainers and people that previously touched the related code and @ mention them in a comment.
2. Ask on the NixOS Discourse.
3. Ask on the #nixos channel on irc.freenode.net.

[gadtfly]

I'm currently grappling with this.

• According to the manpage for udevadm, possible "actions"/"types of event" are: add remove change move online offline bind unbind

• The udev rule installed by alsa-utils is written to trigger on add

• udevadm test does not run the things specified in the rules, it only shows you what would run

  By default, it tests actions with add

  When I run sudo udevadm test /sys/devices/pci0000:00/0000:00:1b.0/sound/card0/controlC0, I get a similar output to what @lopsided98 pasted above, with a line indicating that alsactl restore would run

• udevadm trigger does run the things specified in the rules

  By default, it triggers actions with change (not add)

  When I run sudo udevadm trigger (not necessary to specify a particular thing, it just triggers everything), checking alsamixer reflects that alsactl restore has not run

  When I run sudo udevadm trigger --action add, checking alsamixer reflects that alsactl restore has run (ie, it worked, and the volume is restored to the previously saved state)

[gadtfly]

I did some very crude printf-debugging and found that my system is executing the first RUN+="..." command in etc/udev/rule.d/90-alsa-restore.rules sometime during system boot, so my previous comment may be a bit of a red herring.

How about: does something else need to be in place before alsactl restore will work?

[lopsided98]

I just tested a machine running about a month old version of nixpkgs master and I can't reproduce this issue anymore. @gadtfly What nixpkgs version are you testing?

[gadtfly]

Thanks for checking.

To be completely honest, I'm not sure how to determine that or what precisely that means.

I installed this system from the 21.05 Graphical ISO some time around June 30th, I haven't explicitly done anything to do with channels, and I've run nixos-rebuild switch a bunch times while connected to the internet. My nixpkgs version is in whatever state that would leave me in.

[gadtfly]

Here's where I'm at with this issue on my system:

• Booting the system successfully runs 90-alsa-restore.rules
• That 90-alsa-restore.rules run successfully runs alsactl restore
• That alsactl restore run successfully restores the previously-saved ALSA volume
• PulseAudio starting or restarting resets the ALSA volume to its default value (undoing any alsactl restore, or manual alsamixer changes, or whatever)

[gadtfly]

Here's the workaround that I'm trying:

systemd.user.services.alsa-restore-fix = {
  after = [ "pulseaudio.service" ];
  wantedBy = [ "pulseaudio.service" ];
  script = "${pkgs.alsaUtils}/bin/amixer -c1 sset 'Speaker' 39";
};

I am not particularly familiar with writing systemd units so I have no idea if this is the "right" way to do this, but it seems to work.

I couldn't (sufficiently easily) figure out how to get a system-wide service to trigger on PulseAudio start (which happens per-user), so this is a user service.

I couldn't (sufficiently easily) figure out how to get alsactl restore (which requires root permissions) to work in a user service, so I'm just setting the volume directly.

39 is 100% on this thing (the default it kept resetting to was 10, which is 26%). The intention was always to manage the volume with PulseAudio. This seems to work so far.

[lopsided98]

Yeah, I'm pretty sure that is a different issue than mine, unless perhaps PulseAudio was implicitly enabled somewhere in my config. My machines that had this issue were headless, and did not intentionally enable PulseAudio.

I would guess that PulseAudio is trying to manage the volume itself, and there might be some way of persistently adjusting it from within the PulseAudio settings.

[gadtfly]

I'm starting to suspect that the root problem for me is that PulseAudio is not hooking itself in to my audio card's volume in the way it may be supposed to (I don't know, I'm not particularly famliar with PulseAudio either).

You're right that does seem to be a different issue.

Thank you for your help!

[stale[bot]]

I marked this as stale due to inactivity. → More info

[mastarija]

Any update on this? I'm having problems with alsa settings not being restored on startup.

[Baitinq]

Having this problem too

[lykso]

I am also having this problem. I found a workaround, but my machine is a little unusual so YMMV. You'll likely want to leave out line 138, at any rate, as that's specific to my particular setup.

The workaround, minus line 138, for your convenience:

services.udev.extraRules = ''
ACTION=="add", SUBSYSTEM=="sound", KERNEL=="controlC*", KERNELS!="card*", TEST="${pkgs.alsa-utils}", TEST="/var/lib/alsa/asound.state, GOTO="alsa_restore_go", GOTO="alsa_restore_end"

LABEL="alsa_restore_go"
TEST!="/etc/alsa/state-daemon.conf",RUN+="${pkgs.alsa-utils}/bin/alsactl restore $attr{device/number}"
TEST=="/etc/alsa/state-daemon.conf",RUN+="${pkgs.alsa-utils}/bin/alsactl nrestore $attr{device/number}"

LABEL="alsa_restore_end"
'';

[tupo2]

Other workaround if PulseAudio is installed:

Edit the file /usr/share/pulseaudio/alsa-mixer/paths/analog-output.conf.common (on Debian) Add or modify those element examples to not be altered by PulseAudio:

[Element Master]
switch = ignore
volume = ignore

[Element PCM]
switch = ignore
volume = ignore

[Element Front]
switch = ignore
volume = ignore

There is an equivalent for PipeWire.