[PATCH] drm/i915: Lock timeline mutex directly in error path of eb_pin_timeline

[Matthew Brost]

Don't use the interruptable version of the timeline mutex lock in the
error path of eb_pin_timeline as the cleanup must always happen.

v2:
 (John Harrison)
  - Don't check for interrupt during mutex lock
v3:
 (Tvrtko)
  - A comment explaining why lock helper isn't used

Fixes: 544460c33821 ("drm/i915: Multi-BB execbuf")
Signed-off-by: Matthew Brost <matthew.br...@intel.com>
---
 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c 
b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
index 9e221ce427075..4a611d62e991a 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
@@ -2518,9 +2518,14 @@ static int eb_pin_timeline(struct i915_execbuffer *eb, 
struct intel_context *ce,
                                      timeout) < 0) {
                        i915_request_put(rq);
 
-                       tl = intel_context_timeline_lock(ce);
+                       /*
+                        * Error path, cannot use intel_context_timeline_lock as
+                        * that is user interruptable and this clean up step
+                        * must be done.
+                        */
+                       mutex_lock(&ce->timeline->mutex);
                        intel_context_exit(ce);
-                       intel_context_timeline_unlock(tl);
+                       mutex_unlock(&ce->timeline->mutex);
 
                        if (nonblock)
                                return -EWOULDBLOCK;
-- 
2.34.1