Bug 217440

Summary: ALC236 audio disappears from HP 15z-fc000 on warm boot
Product: Drivers Reporter: Joseph C. Sible (josephcsible)
Component: Sound(ALSA)Assignee: Jaroslav Kysela (perex)
Status: NEW ---    
Severity: normal CC: arsilq, mitsuriakagi
Priority: P3    
Hardware: All   
OS: Linux   
Kernel Version: 6.3.2 Subsystem:
Regression: Yes Bisected commit-id: 5aec98913095ed3b4424ed6c5fdeb6964e9734da

Description Joseph C. Sible 2023-05-13 19:46:47 UTC
On an HP 15z-fc000 laptop that uses Realtek ALC236 for sound, once the system is warm booted ("reboot" from within Linux), sound stops working completely and the device doesn't even show up anymore. Once this happens, the only way to get it to come back is to cold boot ("poweroff" from within Linux, wait for it to turn completely off, and turn it back on with the physical power button). In particular, once you boot from a "bad" kernel, no number of warm boots with "good" kernels will ever bring sound back.

I bisected this to commit 5aec989, which first appeared in 5.15-rc6. In addition, I confirmed by doing a custom build of 6.3.2 with reverts of both f30741c (just to avoid a conflict) and 5aec989, which works correctly for me.