Commit-ID: c7faee2109f978f3ef826c48b7e60609061fda4f
Gitweb: http://git.kernel.org/tip/c7faee2109f978f3ef826c48b7e60609061fda4f
Author: Ingo Molnar <mi...@kernel.org>
AuthorDate: Thu, 3 Nov 2016 07:16:43 +0100
Committer: Ingo Molnar <mi...@kernel.org>
CommitDate: Thu, 3 Nov 2016 07:21:12 +0100
locking/drm: Fix i915_gem_shrinker_lock() locking
Mike Krinkin reported hangs in the DRM code and bisected it to:
3ab7c086d5ec72585ef0 ("locking/drm: Kill mutex trickery")
Hugh Dickins observed:
"i915_gem_shrinker_lock() is broken: but copy the pattern from
msm_gem_shrinker_lock() and it's okay - patch below."
Pick up the fix in isolation to make sure the bug is fixed, cleanup
patch will follow up.
Originally-From: Hugh Dickins <hu...@google.com>
Reported-by: Hugh Dickins <hu...@google.com>
Reported-by: Mike Krinkin <krinkin....@gmail.com>
Cc: Andrew Morton <a...@linux-foundation.org>
Cc: Dave Airlie <airl...@redhat.com>
Cc: Linus Torvalds <torva...@linux-foundation.org>
Cc: Paul E. McKenney <paul...@linux.vnet.ibm.com>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Thomas Gleixner <t...@linutronix.de>
Cc: ch...@chris-wilson.co.uk
Cc: jason.l...@hpe.com
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.1610301645180.28429@eggly.anvils
Signed-off-by: Ingo Molnar <mi...@kernel.org>
---
drivers/gpu/drm/i915/i915_gem_shrinker.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/i915/i915_gem_shrinker.c
b/drivers/gpu/drm/i915/i915_gem_shrinker.c
index 3695375..e9bd2a8 100644
--- a/drivers/gpu/drm/i915/i915_gem_shrinker.c
+++ b/drivers/gpu/drm/i915/i915_gem_shrinker.c
@@ -228,8 +228,9 @@ unsigned long i915_gem_shrink_all(struct drm_i915_private
*dev_priv)
static bool i915_gem_shrinker_lock(struct drm_device *dev, bool *unlock)
{
if (!mutex_trylock(&dev->struct_mutex))
- *unlock = false;
+ return false;
+ *unlock = true;
return true;
}
