Attachment 129979 Details for Bug 96781 – Don't fall over flip_done failures that hard

[patch] Don't fall over flip_done failures that hard

0001-drm-atomic-helpers-Make-nonblocking-more-resilient.patch (text/plain), 1.74 KB, created by Daniel Vetter on 2017-02-28 10:11:32 UTC

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Creator: Daniel Vetter

Created: 2017-02-28 10:11:32 UTC

Size: 1.74 KB

patch

obsolete

>From 815927c913db732b7998fe89ea7eb97a87013b36 Mon Sep 17 00:00:00 2001
>From: Daniel Vetter <daniel.vetter@ffwll.ch>
>Date: Tue, 28 Feb 2017 11:06:50 +0100
>Subject: [PATCH] drm/atomic-helpers: Make nonblocking more resilient
>
>We've switched to refcounting for the event completion, which means
>there's no risk for use-after free anymore after:
>
>commit 24835e442f289813aa568d142a755672a740503c
>Author: Daniel Vetter <daniel.vetter@ffwll.ch>
>Date:   Wed Dec 21 11:23:30 2016 +0100
>
>    drm: reference count event->completion
>
>This should make the commit machinery a bit more resilient against
>drivers bugs. It won't fix any driver bugs of course.
>
>References: https://bugs.freedesktop.org/show_bug.cgi?id=96781
>Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
>---
> drivers/gpu/drm/drm_atomic_helper.c | 9 +++++----
> 1 file changed, 5 insertions(+), 4 deletions(-)
>
>diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
>index 9203f3e933f7..f68181a92210 100644
>--- a/drivers/gpu/drm/drm_atomic_helper.c
>+++ b/drivers/gpu/drm/drm_atomic_helper.c
>@@ -1611,15 +1611,16 @@ void drm_atomic_helper_commit_cleanup_done(struct drm_atomic_state *old_state)
> 
> 		spin_unlock(&crtc->commit_lock);
> 
>-		/* We must wait for the vblank event to signal our completion
>-		 * before releasing our reference, since the vblank work does
>-		 * not hold a reference of its own. */
> 		ret = wait_for_completion_timeout(&commit->flip_done,
> 						  10*HZ);
>-		if (ret == 0)
>+		if (ret == 0) {
> 			DRM_ERROR("[CRTC:%d:%s] flip_done timed out\n",
> 				  crtc->base.id, crtc->name);
> 
>+			/* Unblock at least subsequent commits */
>+			complete_all(&commit->flip_done);
>+		}
>+
> 		spin_lock(&crtc->commit_lock);
> del_commit:
> 		list_del(&commit->commit_entry);
>-- 
>2.11.0
>

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Attachments on bug 96781: 127582 | 127741 | 128085 | 128603 | 128686 | 128882 | 129266 | 129434 | 129979 | 130168 | 131280 | 131591

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