6.6-stable review patch. If anyone has any objections, please let me know.
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From: Zack Rusin zack.rusin@broadcom.com
commit a60ccade88f926e871a57176e86a34bbf0db0098 upstream.
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@broadcom.com Fixes: 06ec41909e31 ("drm/vmwgfx: Add and connect CRTC helper functions") Cc: Broadcom internal kernel review list bcm-kernel-feedback-list@broadcom.com Cc: dri-devel@lists.freedesktop.org Cc: stable@vger.kernel.org # v4.12+ Reviewed-by: Ian Forbes ian.forbes@broadcom.com Reviewed-by: Martin Krastev martin.krastev@broadcom.com Link: https://patchwork.freedesktop.org/patch/msgid/20240412025511.78553-5-zack.ru... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/vmwgfx/vmwgfx_kms.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-)
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c @@ -926,6 +926,7 @@ int vmw_du_cursor_plane_atomic_check(str 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); @@ -933,9 +934,13 @@ int vmw_du_crtc_atomic_check(struct drm_ 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 &&