From: Rob Clark <robdclark@gmail.com>
Date: Sat, 8 Nov 2014 15:16:19 +0000 (-0500)
Subject: drm/irq: BUG_ON() -> WARN_ON()
X-Git-Tag: v3.16.49~37
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ac500cd3863d7f89c448d77416b5fb25b2c734bc;p=thirdparty%2Fkernel%2Fstable.git

drm/irq: BUG_ON() -> WARN_ON()

commit 7f907bf284ba7bb8d271f094b226699d3fef2142 upstream.

Let's make things a bit easier to debug when things go bad (potentially
under console_lock).

Signed-off-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---

diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index 0de123afdb346..990e5ac8b18d0 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -973,7 +973,8 @@ EXPORT_SYMBOL(drm_crtc_vblank_get);
  */
 void drm_vblank_put(struct drm_device *dev, int crtc)
 {
-	BUG_ON(atomic_read(&dev->vblank[crtc].refcount) == 0);
+	if (WARN_ON(atomic_read(&dev->vblank[crtc].refcount) == 0))
+		return;
 
 	/* Last user schedules interrupt disable */
 	if (atomic_dec_and_test(&dev->vblank[crtc].refcount) &&