Bug 935232 – >=media-video/pipewire-1.0.7 - "pipewire[3309]: segfault at 10 ip 00007f1d525c65ce sp 00007ffcc5e6eef8 error 4 in libc.so" at start and failing to detect audio devices (on musl)

• Status: RESOLVED INVALID
• Product: Gentoo Linux

[Description ernsteiswuerfel 2024-06-30 14:26:06 UTC]

Created attachment 896656 [details]
build.log (amd64, 9999)

Rebooting after the pipewire-1.0.7 + wireplumber-0.5.3 stable upgrade I got no sound and no audio devices showed up (wpctl status only shows dummy device). The cards do show up in alsactl and alsamixer however.

I also noticed this segfault showing up in /var/log/syslog:
[...]
Jun 30 15:10:11 yea kernel: pipewire[3309]: segfault at 10 ip 00007f1d525c65ce sp 00007ffcc5e6eef8 error 4 in libc.so[7f1d525b1000+66000] likely on CPU 7 (core 3, socket 0)
118072-Jun 30 15:10:11 yea kernel: Code: 74 13 85 c9 74 02 f4 9b 8b 4f f8 81 f9 ff ff 00 00 7f 02 f4 9b 89 c8 83 e2 1f c1 e0 04 48 98 48 29 c7 48 8b 47 f0 48 83 c7 f0 <48> 39 78 10 74 02 f4 9b 8b 70 20 83 e6 1f 39 d6 73 02 f4 9b 8b 78

Tried pipewire-1.2.0, pipewire-9999, wireplumber-0.5.5, wireplumber-9999 but the segfault and the issue remained.

Only downgrading to pipewire-1.0.5 + wireplumber-0.4.17-r1 got me sound back.

Also does not matter whether I build with gcc or clang. But as my glibc system does not show this issue with pipewire-1.0.7 + wireplumber-0.5.3 I suspect this to be a musl issue.

[Comment 1 ernsteiswuerfel 2024-06-30 14:27:04 UTC]

Created attachment 896657 [details]
emerge --info

[Comment 2 Sam James 2024-06-30 14:27:11 UTC]

Could you try to get a backtrace (https://wiki.gentoo.org/wiki/Debugging)?

Even better is if the testsuite fails for you... (either ideally PW or WP at a push).

[Comment 3 ernsteiswuerfel 2024-06-30 16:11:37 UTC]

Turned out the reason for the segfault were stale .config files in /etc/wireplumber.

But you only get the relevant hint when logging is explicitly set in .config/gentoo-pipewire-launcher.conf or when you start wireplumber manually (which is discouraged in https://wiki.gentoo.org/wiki/PipeWire as you should use gentoo-pipewire-launcher).

 $ cat .config/gentoo-pipewire-launcher.conf 
GENTOO_PIPEWIRE_LOG=~/pw.log
GENTOO_WIREPLUMBER_LOG=~/wp.log

 $ cat wp.log 
[2024-06-30T18:04:57CEST] Starting WirePlumber.
Failed to load configuration: The configuration file at '/etc/wireplumber/wireplumber.conf' is likely an old WirePlumber 0.4 config and is not supported anymore. Try removing it.

Without logging you only get the segfault which leaves one a bit clueless at first...

Once the old config is deleted in /etc/wireplumber and the default wireplumber-0.5.3 config is used the segfault is gone too and audio devices are correctly discovered.