alsa-ucm-conf VS systemd

This is the place to start - https://github.com/alsa-project/alsa-ucm-conf

Well I kinda asked about i3 related problems not just generic linux desktop voes but I'll try my best.

> - I recently bought a monitor and plugged it in. Sound stopped working until I rebooted. Figured it out easily with pavucontrol of course (just toggling things) but only after reboot. Annoying but fair enough.

And that isn't a problem under GNOME ? Both use Pulseaudio...

Anyway I ended up resorting to writing some custom udev rules and some horrible hacks [0] to get my sound interface to work correctly; the interface was 2 in/4 out but it showed up as stereo in/4.0 out, and I needed dual mono + dual stereo outs. But as pulseaudio have no memory whatsoever on plugin config, it needs to be reapplied any time device is plugged in...

...and after upgrade ALSA of all things horribly broke it in different way [1], where someone added 500ms latency to default profile used to split device into sub-channels to"fix cracking" (that happened to only some users), and the interface I used was assigned that profile

Linux Sound story is by far my least liked part of it. And the new modern pipewire just hangs on my machine, not accepting any commands...

> Connecting/disconnecting monitors is flaky, sometimes it requires a few toggles in arandr (which already helps a lot). Maybe there is a better tool I could use?

I so far only experienced it with one flaky monitor at work, it looks like some deeply rooted problem. I guess if I had to solve it I'd just make some script trying to apply the profile and bind it to keys to quickly fix it. I don't think arandr is the culprit here, rather something between graphics server, driver, and monitor.

> Some wifi networks sometimes dont' work out of the box even though I'm just using the easy nm-applet.

I didn't had that problem in particular on laptop at least (also using nm-applet), but same thing works under GNOME ? IIRC it also uses network manager. We had some problems with users trying to use networkmanager for VPN and it not supporting all options plain OpenVPN did.

The most grief that networking gave me is actually systemd-resolved [2] but no good fix for that so far.

- [0] https://devrandom.eu/blog/post/2022-11-03_splitting_stereo_i...

- [1] https://github.com/alsa-project/alsa-ucm-conf/issues/192#iss...

- [2] https://github.com/systemd/systemd/issues/27543

But on the flip-side, if you don't use SteamOS, it's a lot of effort to cobble together all the optimizations that make the Steam Deck great (not just the custom kernel--as you can now use the mainline kernel and a quick patch), but the TDP/clock/fps limiters you can slide up and down from that side menu.

Yes. I am using omni directional. Fixed here: https://github.com/alsa-project/alsa-ucm-conf/issues/308

I have the MOTU M2 on Manjaro Linux and it works fine through Jack. I know there were some issues with having it recognized under Pulseaudio (here and here), but I think those have been fixed. I sometimes have to power cycle the M2 before it's recognized under Pulseaudio again.

Googling the issue I found I'm not the only one with issues surrounding that chip. I came across this issue, which led me to add my specific device ID (of course it's different for each model 🤦) to my /usr/share/alsa/ucm2/USB-Audio/USB-Audio.conf, without notable effect. Yes I rebooted. I also came across this PR, but I haven't been able to figure out if there's a change I can make to my local files that would make the ALC4080-HiFi driver feel responsible for this USB device, if it's even relevant.

Most probably something todo with recent alsa ucm changes for M4:https://github.com/alsa-project/alsa-ucm-conf/blob/master/ucm2/USB-Audio/MOTU/M4.conf If changing profiles in pavucontrol on Configuration tab does not help, you can try to disable ucm: https://wiki.archlinux.org/title/PipeWire#Microphone_is_not_detected_by_PipeWire

You can check https://github.com/alsa-project/alsa-ucm-conf

I've had a kernel update break my sound card, alsa-ucm break my sound card and I also experienced the grub problem, which was a pain. I update yesterday and now OpenCL is broken for what I needed it for (hashcat). None I can blame on Arch, it just happens when you get new stuff. Fedora also updated to those packages that broke my sound card, which is typically my Fedora experience after switching from Arch. You get the same bugs.. just a bit later. Not sure what I'll even try now.

No, the OP was not sent any harassment, the OP _did_ the harassment as it can be seen in the tweets. I mean, they are right there, just click on the links you shared. One of the OP's followers even openly called for the assassination of the project maintainer, and you have the galls to defend him? This is truly deranged stuff.

And again, there is no "vulnerability", there is simply a person that doesn't know how Linux works and has learned something new. Which again it's fine, nobody knows everything and we all learn new things everyday, it's just that normal and sensible people don't use that to make grand claims on social media and start harassment campaigns culminating in death threats.

Professional security researchers responsibly report real issues using the appropriate channels, such as defined at: https://github.com/systemd/systemd/security/policy this is not the work of a researcher, this is a grifter looking for self-promotion on social media.

> 3. even `adduser` will not allow it by default

5. useradd does allow it (as noted in a comment). 6. Local users are not the only source, there things like LDAP and AD.

7. POSIX allows it:

* https://github.com/systemd/systemd/issues/6237#issuecomment-...

> I for one love to type out 13 extra characters

FWIW, systemd is normally pretty good at providing autocomplete suggestions, so even if you don't want to set up an alias you'll probably just have to type `--b ` to set it.

> I wonder what random ASCII escape sequences we can send.

According to the man page source[0]:

> The color specified should be an ANSI X3.64 SGR background color, i.e. strings such as `40`, `41`, …, `47`, `48;2;…`, `48;5;…`

and a link to the relevant Wikipedia page[1]. Given systemd's generally decent track record wrt defects and security issues, and the simplicity of valid colour values, I expect there's a fairly robust parameter verifier in there.

In fact, given the focus on starting the elevated command in a highly controlled environment, I'd expect the colour codes to be output to the originating terminal, not forwarded to the secure pty. That way, the only thing malformed escapes can affect is your own process, which you already have full control over anyway.

(Happy to be shown if that's a mistaken expectation though.)

[0] https://github.com/systemd/systemd/blob/main/man/run0.xml

[1] https://en.wikipedia.org/wiki/ANSI_escape_code#SGR_(Select_G...

bash & zsh are supported by upstream: https://github.com/systemd/systemd/tree/main/shell-completio...

the right person to replace sudo, not: https://github.com/systemd/systemd/issues/6237

PS: https://pwnies.com/systemd-bugs/

https://github.com/systemd/systemd/issues/32028#issuecomment...

There are some very compelling arguments made there if you care to read them

Maybe it was because you weren't pointing out anything new?

There was a pull request to stop linking libzma to systemd before the attack even took place

https://github.com/systemd/systemd/pull/31550

This was likely one of many things that pushed the attackers to work faster, and forced them into making mistakes.

The PR for changing compression libraries to use dlopen() was opened several weeks before the xz-utils backdoor was revealed.

https://github.com/systemd/systemd/pull/31550