From 9334ef755f060e251f3f395caeda1a58b6834ea3 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Fri, 28 Jan 2011 11:53:03 +0000 Subject: [PATCH] drm: Don't switch fb when disabling an output In drm_crtc_helper_set_config, we call drm_crtc_helper_set_mode which may return early and do no operation if the crtc is to be disabled. In this case we merrily swap to the new fb, discarding the old_fb believing that it has been cleaned up. However, due to the early return, the old_fb was not presented to the backend for correct reaping, and nor was the new one - which is about to be reaped via the drm_helper_disable_unused_functions(), leading to incorrect refcounting of the pinned objects. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=27722 Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=29857 Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=29230 Tested-by: Takashi Iwai Signed-off-by: Chris Wilson --- drivers/gpu/drm/drm_crtc_helper.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/drm_crtc_helper.c b/drivers/gpu/drm/drm_crtc_helper.c index 952b3d4fb2a6..468e8e16c806 100644 --- a/drivers/gpu/drm/drm_crtc_helper.c +++ b/drivers/gpu/drm/drm_crtc_helper.c @@ -649,8 +649,8 @@ int drm_crtc_helper_set_config(struct drm_mode_set *set) mode_changed = true; if (mode_changed) { - set->crtc->enabled = (set->mode != NULL); - if (set->mode != NULL) { + set->crtc->enabled = drm_helper_crtc_in_use(set->crtc); + if (set->crtc->enabled) { DRM_DEBUG_KMS("attempting to set mode from" " userspace\n"); drm_mode_debug_printmodeline(set->mode); -- 2.20.1