[PATCH 0/3] drm/client: Wire up sysrq for all clients and update drm_log

Thomas Zimmermann
2025-11-07T14:26:18Z

DRM's fbdev emulation has long supported SysRq+v to bring up the
framebuffer console for emergency output. Wire up sysrq for all
DRM clients and make it work with drm_log.

Patch 1 and 2 set up DRM client functionality for sysrq. The patches
adopt existing conventions from fbdev emulation, so that there's no
visible change to users. Invoke SysRq+v to bring up the in-kernel DRM
client.

Patch 3 adds restore functionality to drm_log. This enables SysRq, but
also brings back drm_log when the user-space releases control of the
display.

Tested on amdgpu and bochs.

Thomas Zimmermann (3):
drm/client: Pass force parameter to client restore
drm/client: Support emergency restore via sysrq for all clients
drm/client: log: Implement struct drm_client_funcs.restore

drivers/gpu/drm/Makefile | 3 +-
drivers/gpu/drm/clients/drm_fbdev_client.c | 6 +-
drivers/gpu/drm/clients/drm_log.c | 13 ++++
drivers/gpu/drm/drm_client.c | 1 +
drivers/gpu/drm/drm_client_event.c | 4 +-
drivers/gpu/drm/drm_client_sysrq.c | 65 ++++++++++++++++++++
drivers/gpu/drm/drm_drv.c | 3 +
drivers/gpu/drm/drm_fb_helper.c | 69 +++-------------------
drivers/gpu/drm/drm_file.c | 2 +-
drivers/gpu/drm/drm_internal.h | 11 ++++
include/drm/drm_client.h | 8 ++-
include/drm/drm_client_event.h | 4 +-
include/drm/drm_device.h | 8 +++
include/drm/drm_fb_helper.h | 8 +--
14 files changed, 126 insertions(+), 79 deletions(-)
create mode 100644 drivers/gpu/drm/drm_client_sysrq.c

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2.51.1