This is a note to let you know that I've just added the patch titled
drm/vmwgfx: Fix crtc's atomic check conditional
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
drm-vmwgfx-fix-crtc-s-atomic-check-conditional.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit d8eb1ccd25a13cf4a991fb53e515a59d9728e747
Author: Zack Rusin <zack.rusin@xxxxxxxxxxxx>
Date: Thu Apr 11 22:55:10 2024 -0400
drm/vmwgfx: Fix crtc's atomic check conditional
[ Upstream commit a60ccade88f926e871a57176e86a34bbf0db0098 ]
The conditional was supposed to prevent enabling of a crtc state
without a set primary plane. Accidently it also prevented disabling
crtc state with a set primary plane. Neither is correct.
Fix the conditional and just driver-warn when a crtc state has been
enabled without a primary plane which will help debug broken userspace.
Fixes IGT's kms_atomic_interruptible and kms_atomic_transition tests.
Signed-off-by: Zack Rusin <zack.rusin@xxxxxxxxxxxx>
Fixes: 06ec41909e31 ("drm/vmwgfx: Add and connect CRTC helper functions")
Cc: Broadcom internal kernel review list <bcm-kernel-feedback-list@xxxxxxxxxxxx>
Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
Cc: <stable@xxxxxxxxxxxxxxx> # v4.12+
Reviewed-by: Ian Forbes <ian.forbes@xxxxxxxxxxxx>
Reviewed-by: Martin Krastev <martin.krastev@xxxxxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20240412025511.78553-5-zack.rusin@xxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
index 01d5a01af2594..e2a52b5de1733 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
@@ -537,6 +537,7 @@ int vmw_du_cursor_plane_atomic_check(struct drm_plane *plane,
int vmw_du_crtc_atomic_check(struct drm_crtc *crtc,
struct drm_atomic_state *state)
{
+ struct vmw_private *vmw = vmw_priv(crtc->dev);
struct drm_crtc_state *new_state = drm_atomic_get_new_crtc_state(state,
crtc);
struct vmw_display_unit *du = vmw_crtc_to_du(new_state->crtc);
@@ -544,9 +545,13 @@ int vmw_du_crtc_atomic_check(struct drm_crtc *crtc,
bool has_primary = new_state->plane_mask &
drm_plane_mask(crtc->primary);
- /* We always want to have an active plane with an active CRTC */
- if (has_primary != new_state->enable)
- return -EINVAL;
+ /*
+ * This is fine in general, but broken userspace might expect
+ * some actual rendering so give a clue as why it's blank.
+ */
+ if (new_state->enable && !has_primary)
+ drm_dbg_driver(&vmw->drm,
+ "CRTC without a primary plane will be blank.\n");
if (new_state->connector_mask != connector_mask &&
