Revert "drm/i915: Fix mutex->owner inspection race under DEBUG_MUTEXES"

The core fix was applied in

commit a63b03e2d2477586440741677ecac45bcf28d7b1
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Tue Jan 6 10:29:35 2015 +0000

    mutex: Always clear owner field upon mutex_unlock()

(note the absence of stable@ tag)

so we can now revert our band-aid commit 226e5ae9e5f910 for -next.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 361d18b..36f1093 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -5099,7 +5099,7 @@ static bool mutex_is_locked_by(struct mutex *mutex, struct task_struct *task)
        if (!mutex_is_locked(mutex))
                return false;
 
-#if defined(CONFIG_SMP) && !defined(CONFIG_DEBUG_MUTEXES)
+#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_MUTEXES)
        return mutex->owner == task;
 #else
        /* Since UP may be pre-empted, we cannot assume that we own the lock */