From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Date: Thu, 27 Aug 2015 11:58:09 +0000 (+0200)
Subject: drm/atomic: Make sure lock is held in trylock contexts.
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=825926d8e0bfa6f933706236603bb74a8cea002c;p=linux-beck.git

drm/atomic: Make sure lock is held in trylock contexts.

This will make sure we get a lockdep spat in all cases
even if the context is a complete garbage pointer.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
---

diff --git a/drivers/gpu/drm/drm_modeset_lock.c b/drivers/gpu/drm/drm_modeset_lock.c
index fba321ca4344..6675b1428410 100644
--- a/drivers/gpu/drm/drm_modeset_lock.c
+++ b/drivers/gpu/drm/drm_modeset_lock.c
@@ -307,6 +307,8 @@ static inline int modeset_lock(struct drm_modeset_lock *lock,
 	WARN_ON(ctx->contended);
 
 	if (ctx->trylock_only) {
+		lockdep_assert_held(&ctx->ww_ctx);
+
 		if (!ww_mutex_trylock(&lock->mutex))
 			return -EBUSY;
 		else