If the crtc is being switched on or off then the semantics of computing the timestampe of the next vblank is somewhat ill-defined. And indeed, the code splats with a warning in the timestamp computation code. Specifically it hits the check to make sure that atomic drivers have full set up the timing constants in the drm_vblank structure, and that's just not the case before the crtc is actually on.
For robustness it seems best to just not set deadlines for modesets. v2: Also skip on inactive crtc (Ville) Link: https://lore.kernel.org/dri-devel/dfc21f18-7e1e-48f0-c05a-d659b9c90...@linaro.org/ Fixes: d39e48ca80c0 ("drm/atomic-helper: Set fence deadline for vblank") Cc: Ville Syrjälä <ville.syrj...@linux.intel.com> Cc: Rob Clark <robdcl...@chromium.org> Cc: Daniel Vetter <daniel.vet...@ffwll.ch> Cc: Maarten Lankhorst <maarten.lankho...@linux.intel.com> Cc: Maxime Ripard <mrip...@kernel.org> Cc: Thomas Zimmermann <tzimmerm...@suse.de> Reported-by: Dmitry Baryshkov <dmitry.barysh...@linaro.org> Tested-by: Dmitry Baryshkov <dmitry.barysh...@linaro.org> # test patch only Cc: Dmitry Baryshkov <dmitry.barysh...@linaro.org> Signed-off-by: Daniel Vetter <daniel.vet...@intel.com> --- drivers/gpu/drm/drm_atomic_helper.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c index f21b5a74176c..d44fb9b87ef8 100644 --- a/drivers/gpu/drm/drm_atomic_helper.c +++ b/drivers/gpu/drm/drm_atomic_helper.c @@ -1528,6 +1528,12 @@ static void set_fence_deadline(struct drm_device *dev, for_each_new_crtc_in_state (state, crtc, new_crtc_state, i) { ktime_t v; + if (drm_atomic_crtc_needs_modeset(new_crtc_state)) + continue; + + if (!new_crtc_state->active) + continue; + if (drm_crtc_next_vblank_start(crtc, &v)) continue; -- 2.40.0