maintainer-feedback requested: [Bug 261218] graphics/drm-devel-kmod screens blacked out, system freeze, around two minutes after waking from sleep

Bugzilla Automation <bugzilla@FreeBSD.org> has asked freebsd-x11 (Nobody)
<x11@FreeBSD.org> for maintainer-feedback:
Bug 261218: graphics/drm-devel-kmod screens blacked out, system freeze, around
two minutes after waking from sleep
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=261218



--- Description ---
Keywords: 

D33887, D33888, drm-kmod, graphics, LinuxKPI, radeonkms, resume, sleep,
suspend, wake

----

At 23:58 yesterday, in bug 261166 comment 9: 

> … Up for four hours, panic-free, …

Three hours and twelve minutes later (03:10:24), I put the computer to sleep
with a script that gracefully exports OpenZFS devices on USB: 

* a mobile hard disk drive that comprises a non-essential pool

* two small (thumb) flash drives that provide L2ARC to the boot pool

– then switched off a display on DisplayPort on the HP dock in which this HP
EliteBook 8570p rests. 

----

At then after 06:23, to the best of my recollection, I: 

* woke the computer

* switched on the display (a little late)

* ran xrandr

* disconnected then remade USB connections to the docked HP keyboard and 
  docked Kensington trackball (one after the other, I can't recall 
  which order, to work around the operating system not responding to 
  one of the two devices)

* maybe also disconnected both devices then reconnected both devices

* rearranged windows – mostly dragging from the notebook display (left)
  to the Philips display (right).

Screens on both displays suddenly went dark (blank/black/grey) with no cursor
or pointer.

I watched the front of the EliteBook for hard disk drive activity. None. 

I have this computer set to gracefully shut down (not sleep) in response to a
press on the power button, which is separate from the keyboard. No response to
normal presses. 

After a while, I forced off the computer, started, then shortly after the
desktop environment (KDE Plasma) appeared I ran: 

hw-probe -all -upload

Result: <https://bsd-hardware.info/?probe=5f106ee686>

I see nothing in X.Org logs (probed, above) or /var/log/messages to indicate
exactly what happened _immediately_ before the freeze occurred. 

This absence of information is unfortunate, but does make sense, in that the
freeze was sudden and complete. 


Triage
======

Tentatively    graphics/drm-devel-kmod	  because I'm testing this in
combination with the patches for (bug 261166) these two reviews: 

⚙ D33887 LinuxKPI: Allow spin_lock_irqsave to be called within a critical
section
<https://reviews.freebsd.org/D33887>

⚙ D33888 LinuxKPI: Allow wake_up to be executed within a critical section
<https://reviews.freebsd.org/D33888>

Cc: the author and reviewers. If this bug is irrelevant: my apologies, please
remove yourselves.

Thank you. 


Notes to self
=============

Four USB ports on the side of the dock: 

* mobile hard disk drive (rear, upper)

* trackball (front, lower)

* keyboard (front, upper).

Two USB ports at the rear of the dock: 

* the lower nearly always runs to the USB hub that's integral to the 
  Philips display … yesterday, extraordinarily, I removed the cable 
  (to rearrange things at the table) and did not replace it

* L2ARC, 15G, Duracell-branded Alcor Micro Flash Drive 
  USB 058f:6387 (upper).

Two ports on the left of the EliteBook: 

* L2ARC, 29G, Kingston Technology DataTraveler 100 G3/G4/SE9 G2/50 
  USB 0951:1666 (front).