14-ALPHA2 panic on cold boot

From: cglogic <cglogic_at_protonmail.com>
Date: Tue, 29 Aug 2023 08:09:03 UTC
Hello dear FreeBSD community,

Recently I tried to boot from FreeBSD 14-ALPHA2 image and got panic on first boot after power on.
My hardware is AMD Ryzen 9 5900X on ASUS ROG STRIX B550-E GAMING.
It's related to audio chip ALC1220 initialization.

If I remember correctly, when I tried FreeBSD 13-STABLE, around 2 years ago, no panic was observed.
But at that time my GPU was unsupported by drm-kmod. So I installed Linux and used it for 2 years.
On Linux, no such a panic observed. Now drm-kmod supports my GPU and I want move to FreeBSD.

Also tried 13.2, got the same panic.
Can't try earlier FreeBSD 13 releases, as they are not available for download anymore.

I found two related bug reports:
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=264305

https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=268393

My backtrace is the same as in reported issues. So I did not write it from a screen to a paper.

As I understand, this bug affects all AMD Zen2, Zen3 and Zen4 computers and laptops.

We are near FreeBSD 14.0 release now, maybe it will be possible to fix it before release.

Thanks.