Re: how to debug suspend/resume crash

[Taylor R Campbell <campbell+netbsd-tech-kern%mumble.net@localhost>]

> Date: Wed, 17 Nov 2021 12:58:54 +0000
> From: Emmanuel Dreyfus <manu%netbsd.org@localhost>
> 
> I am playing with a notebook that has trouble awaking up.
> If try sysctl -w hw.acpi.sleep.state=3 it complains about ihidev0 which
> is unable to suspend.

Is that message `failed to power down', or what?

>                       After I run drvctl -d ihidev, the system accepts
> going to sleep. But it seems unable to wake up. Opening up the lid cause
> the power led to switch on, but nothing else happen.
> 
> How can that be debugged? There is not much information to get from
> a suspended machine.

- Boot with -v -x, verbose and debug.

- Try suspending and resuming different subtrees of devices:
    drvctl -S foo0 && drvctl -Q foo0

- See if you can get a serial console -- even if there's no com port
  exposed, you may be able to get serial-over-LAN with Intel AMT or
  similar.