Re: HEADS UP: Merging drm update

[Taylor R Campbell <riastradh%NetBSD.org@localhost>]

> Date: Sun, 26 Dec 2021 02:37:31 +0900
> From: Ryo ONODERA <ryo%tetera.org@localhost>
> 
> If panic is removed, my LCD turns black finally and stay black forever
> and does not reach to USB serial console.
> [...]
> However I am not sure because I cannot get any message.
> 
> Do you have an idea to investigate deeper?

Does your laptop have anything like Intel AMT which you could use to
get serial-over-LAN?

Maybe you can put in a panic later, after the display changes, and
build your kernel with DDB_COMMANDONENTER="bt;sync", so you might be
able to either (a) get a crash dump or (b) see the last boot's dmesg
when the machine resets (and you then boot an older kernel)?