From: Daniel Vetter Date: Tue, 14 Jun 2016 17:50:58 +0000 (+0200) Subject: drm/atomic-helpers: Stall on the right commit X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=723c3e553051bcb82eb8d8962c04171040068e83;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git drm/atomic-helpers: Stall on the right commit stall_checks carefully picked out the right commit to stall on, then promptly used the wrong variable. Due to the break in the next loop iteration this could be the 3rd commit, or if the list only has 2 entries commit would now point into the struct drm_crtc itself, at some offset. Hilarity eventually ensues. For added safety, also break right away instead of iterating once more, but the real fix is waiting on stall_commit instead of commit. Reported-and-tested-by: Liviu Dudau Cc: Liviu Dudau Signed-off-by: Daniel Vetter Reviewed-by: Liviu Dudau Signed-off-by: Daniel Vetter Link: http://patchwork.freedesktop.org/patch/msgid/1465926658-10110-1-git-send-email-daniel.vetter@ffwll.ch --- diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c index 6a13df8691d4..716aa535eb98 100644 --- a/drivers/gpu/drm/drm_atomic_helper.c +++ b/drivers/gpu/drm/drm_atomic_helper.c @@ -1324,8 +1324,8 @@ static int stall_checks(struct drm_crtc *crtc, bool nonblock) } else if (i == 1) { stall_commit = commit; drm_crtc_commit_get(stall_commit); - } else break; + } i++; } @@ -1337,7 +1337,7 @@ static int stall_checks(struct drm_crtc *crtc, bool nonblock) /* We don't want to let commits get ahead of cleanup work too much, * stalling on 2nd previous commit means triple-buffer won't ever stall. */ - ret = wait_for_completion_interruptible_timeout(&commit->cleanup_done, + ret = wait_for_completion_interruptible_timeout(&stall_commit->cleanup_done, 10*HZ); if (ret == 0) DRM_ERROR("[CRTC:%d:%s] cleanup_done timed out\n",