On Thu, 10 Dec 2015, Daniel Vetter <daniel@xxxxxxxx> wrote: > On Mon, Nov 23, 2015 at 10:25:28AM +0100, Maarten Lankhorst wrote: >> Op 13-11-15 om 14:28 schreef Ander Conselvan De Oliveira: >> > On Thu, 2015-11-12 at 14:58 +0100, Maarten Lankhorst wrote: >> >> Op 12-11-15 om 14:37 schreef Ander Conselvan De Oliveira: >> >>> On Wed, 2015-11-11 at 15:36 +0100, Maarten Lankhorst wrote: >> >>>> When disable_noatomic is called plane_mask is not reliable yet, >> >>>> and plane_state->visible = true even after disabling the primary plane. >> >>> So the stale value of plane_state->visible causes a subsequent modeset to >> >>> enable >> >>> the primary again? >> >> Probably not because it would get recalculated in calc_changes, but it should >> >> really be set to false afterwards. >> > So basically I didn't understand how the wrong value of plane_state->visible >> > causes the bug that was mentioned. I think a brief explanation in the commit >> > message would be good. >> Well, apply with git am --scissors. Same patch but mentioning this. >> >> Is this better? >> ---->8----- >> >> When disable_noatomic is called plane_mask is not correct yet, >> and plane_state->visible = true is left as true after disabling >> the primary plane. >> >> Other planes are already disabled as part of crtc sanitization, only the >> primary is left active. But the plane_mask is not updated here. It gets updated >> during fb takeover in modeset_gem_init, or set to the new value on resume. >> >> This means that to disable the primary plane 1 << drm_plane_index(primary) >> needs to be used. >> >> Afterwards because the crtc is no longer active it's forbidden to keep >> plane_state->visible set, or a WARN_ON in intel_plane_atomic_calc_changes >> triggers. There are other code points that rely on accurate plane_state->visible >> too, so make sure the bool is cleared. > > Oh dear is this a mess :( > > As a bugfix this is Reviewed-by: Daniel Vetter <daniel.vetter@xxxxxxxx> Pushed to drm-intel-fixes, thanks for the patch and review. BR, Jani. > > But we need to bring a _lot_ more sanity to this in -next. Would probably > be better if we keep the primary plane state all consistent, and then > clear both visible and plane_mask when fb reconstruction fails. > > Also, some WARN_ON to bitch about inconsistency between plane_mask and > ->visible in the disable code paths would be good I think. > -Daniel > >> >> >> The other planes are already disabled in intel_sanitize_crtc, so >> they don't have to be handled here. >> >> Cc: stable@xxxxxxxxxxxxxxx #v4.3, v4.2? >> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=92655 >> Tested-by: Tomas Mezzadra <tmezzadra@xxxxxxxxx> >> Signed-off-by: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx> >> --- >> drivers/gpu/drm/i915/intel_display.c | 4 +++- >> 1 file changed, 3 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c >> index b5f7493213b7..bc3282ab5ed2 100644 >> --- a/drivers/gpu/drm/i915/intel_display.c >> +++ b/drivers/gpu/drm/i915/intel_display.c >> @@ -6267,9 +6267,11 @@ static void intel_crtc_disable_noatomic(struct drm_crtc *crtc) >> WARN_ON(intel_crtc->unpin_work); >> >> intel_pre_disable_primary(crtc); >> + >> + intel_crtc_disable_planes(crtc, 1 << drm_plane_index(crtc->primary)); >> + to_intel_plane_state(crtc->primary->state)->visible = false; >> } >> >> - intel_crtc_disable_planes(crtc, crtc->state->plane_mask); >> dev_priv->display.crtc_disable(crtc); >> intel_crtc->active = false; >> intel_update_watermarks(crtc); >> -- 2.1.0 >> >> _______________________________________________ >> Intel-gfx mailing list >> Intel-gfx@xxxxxxxxxxxxxxxxxxxxx >> http://lists.freedesktop.org/mailman/listinfo/intel-gfx -- Jani Nikula, Intel Open Source Technology Center _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
