[PATCH drm] Revert "drm/nouveau/disp: Set drm_mode_config_funcs.atomic_(check|commit)"

[PATCH drm] Revert "drm/nouveau/disp: Set drm_mode_config_funcs.atomic_(check|commit)"

[John Ogness]

This reverts commit 604826acb3f53c6648a7ee99a3914ead680ab7fb.

Apparently there is more to supporting atomic modesetting than
providing atomic_(check|commit) callbacks. Before this revert:

WARNING: [] drivers/gpu/drm/drm_plane.c:389 at .__drm_universal_plane_init+0x13c/0x794 [drm], CPU#1: modprobe/1790
BUG: Kernel NULL pointer dereference on read at 0x00000000
.drm_atomic_get_plane_state+0xd4/0x210 [drm] (unreliable)
.drm_client_modeset_commit_atomic+0xf8/0x338 [drm]
.drm_client_modeset_commit_locked+0x80/0x260 [drm]
.drm_client_modeset_commit+0x40/0x7c [drm]
.__drm_fb_helper_restore_fbdev_mode_unlocked.part.0+0xfc/0x108 [drm_kms_helper]
.drm_fb_helper_set_par+0x8c/0xb8 [drm_kms_helper]
.fbcon_init+0x31c/0x618
[...]
.__drm_fb_helper_initial_config_and_unlock+0x474/0x7f4 [drm_kms_helper]
.drm_fbdev_client_hotplug+0xb0/0x120 [drm_client_lib]
.drm_client_register+0x88/0xe4 [drm]
.drm_fbdev_client_setup+0x12c/0x19b4 [drm_client_lib]
.drm_client_setup+0x15c/0x18c [drm_client_lib]
.nouveau_drm_probe+0x19c/0x268 [nouveau]

Fixes: 604826acb3f5 ("drm/nouveau/disp: Set drm_mode_config_funcs.atomic_(check|commit)")
Reported-by: John Ogness <john.ogness@linutronix.de>
Closes: https://lore.kernel.org/lkml/87ldhf1prw.fsf@jogness.linutronix.de
Signed-off-by: John Ogness <john.ogness@linutronix.de>
---
 drivers/gpu/drm/nouveau/nouveau_display.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/nouveau_display.c b/drivers/gpu/drm/nouveau/nouveau_display.c
index 829c2b573971c..00515623a2cc7 100644
--- a/drivers/gpu/drm/nouveau/nouveau_display.c
+++ b/drivers/gpu/drm/nouveau/nouveau_display.c
@@ -352,8 +352,6 @@ nouveau_user_framebuffer_create(struct drm_device *dev,
 
 static const struct drm_mode_config_funcs nouveau_mode_config_funcs = {
 	.fb_create = nouveau_user_framebuffer_create,
-	.atomic_commit = drm_atomic_helper_commit,
-	.atomic_check = drm_atomic_helper_check,
 };
 
 

base-commit: 63804fed149a6750ffd28610c5c1c98cce6bd377
-- 
2.47.3

Re: [PATCH drm] Revert "drm/nouveau/disp: Set drm_mode_config_funcs.atomic_(check|commit)"

[Daniel Palmer]

Hi John,

On Fri, 30 Jan 2026 at 20:32, John Ogness <john.ogness@linutronix.de> wrote:
>
> This reverts commit 604826acb3f53c6648a7ee99a3914ead680ab7fb.

This seems to fix the boot crash on my sun ultra 5[0] with a geforce 6200.

Tested-by: Daniel Palmer <daniel@thingy.jp>

0 - https://gist.github.com/fifteenhex/0255982bcd76e8b2f53e15f809c2b6ed

Re: [PATCH drm] Revert "drm/nouveau/disp: Set drm_mode_config_funcs.atomic_(check|commit)"

[Danilo Krummrich]

On Fri Jan 30, 2026 at 12:32 PM CET, John Ogness wrote:
> This reverts commit 604826acb3f53c6648a7ee99a3914ead680ab7fb.
>
> Apparently there is more to supporting atomic modesetting than
> providing atomic_(check|commit) callbacks. Before this revert:
>
> WARNING: [] drivers/gpu/drm/drm_plane.c:389 at .__drm_universal_plane_init+0x13c/0x794 [drm], CPU#1: modprobe/1790
> BUG: Kernel NULL pointer dereference on read at 0x00000000
> .drm_atomic_get_plane_state+0xd4/0x210 [drm] (unreliable)
> .drm_client_modeset_commit_atomic+0xf8/0x338 [drm]
> .drm_client_modeset_commit_locked+0x80/0x260 [drm]
> .drm_client_modeset_commit+0x40/0x7c [drm]
> .__drm_fb_helper_restore_fbdev_mode_unlocked.part.0+0xfc/0x108 [drm_kms_helper]
> .drm_fb_helper_set_par+0x8c/0xb8 [drm_kms_helper]
> .fbcon_init+0x31c/0x618
> [...]
> .__drm_fb_helper_initial_config_and_unlock+0x474/0x7f4 [drm_kms_helper]
> .drm_fbdev_client_hotplug+0xb0/0x120 [drm_client_lib]
> .drm_client_register+0x88/0xe4 [drm]
> .drm_fbdev_client_setup+0x12c/0x19b4 [drm_client_lib]
> .drm_client_setup+0x15c/0x18c [drm_client_lib]
> .nouveau_drm_probe+0x19c/0x268 [nouveau]
>
> Fixes: 604826acb3f5 ("drm/nouveau/disp: Set drm_mode_config_funcs.atomic_(check|commit)")
> Reported-by: John Ogness <john.ogness@linutronix.de>
> Closes: https://lore.kernel.org/lkml/87ldhf1prw.fsf@jogness.linutronix.de
> Signed-off-by: John Ogness <john.ogness@linutronix.de>

Applied to drm-misc-fixes, thanks!