CVS commit: src/sys/external/bsd/drm2

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

Module Name:    src
Committed By:   riastradh
Date:           Sun Dec 19 12:04:59 UTC 2021

Modified Files:
        src/sys/external/bsd/drm2/dist/drm: drm_fb_helper.c
        src/sys/external/bsd/drm2/include/drm: drm_client.h

Log Message:
drm: Work around client modeset mutex for entering ddb.

Linux introduced a wait lock (`mutex') around access to the drm
client modesets, even for drm_fb_helper_debug_enter/leave -- which
happen when we're crashing and can't wait for the scheduler to let
whatever thread might hold a mutex continue to run.

This really shouldn't be a wait lock, but disentangling the lock
order and sleeping allocations is difficult, so let's just hope that
it's safe to access unlocked in ddb for now.


To generate a diff of this commit:
cvs rdiff -u -r1.24 -r1.25 src/sys/external/bsd/drm2/dist/drm/drm_fb_helper.c
cvs rdiff -u -r1.1 -r1.2 src/sys/external/bsd/drm2/include/drm/drm_client.h

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.