Re: port-amd64/56844: delete auto-modified network route crash

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

> Date: Wed, 18 May 2022 14:00:00 +0000 (UTC)
> From: ocb@dc.localdomain
> 
> Finally if we try to remove this route by executing 'route delete
> 192.168.88.2 192.168.88.2', machine running KASLR kernel will be
> very limited, X continues to be visually responsive, already running
> terminal emulators can run commands but will hang and can not be
> paused or killed. New terminal emulators can not be started.
> Changing active virtual console will finally crash X and kernel. I
> am not experienced with crashes but this appears like memory is
> slowly getting corrupted. Kernel crash dump successfully gets saved
> to swap, but upon reboot is unable to retrieve it from swap. Note,
> crash dump saving and retrieving works fine on non-kaslr kernel, but
> not in this situation, since..

Do you have a serial console, or a working network interface where you
can redirect output via netcat?

Can you start crash(8) running before triggering this (with output to
serial console or netcat), and, when it starts to hang, type `ps' at
crash(8)?  And, if any threads listed there are in `tstile' or are
marked with a `>' on the line, can you type `bt/a 0xffff...' at
crash(8), where 0xffff... is the lwp address shown in ps output?