[PATCH] drm/i915/gt: Handle INTEL_WAKEREF_DEF return value in gen8_ggtt_bind_get_ce

[Ingyu Jang]

The function 'gen8_ggtt_bind_get_ce' previously did not handle the case
where 'intel_gt_pm_get_if_awake()' returns 'INTEL_WAKEREF_DEF'.
This value is returned when the 'intel_ref_tracker_alloc()' call within
'intel_gt_pm_get_if_awake()' fails to allocate due
to memory pressure or other constraints.

'intel_ref_tracker_alloc()' uses 'ref_tracker_alloc()' with the
'GFP_NOWAIT' flag, which can return 'NULL' if allocation fails.
In this case, the function explicitly returns 'INTEL_WAKEREF_DEF'.

This patch adds a check for 'INTEL_WAKEREF_DEF' in
'gen8_ggtt_bind_get_ce' to ensure that such errors are properly handled.
If 'INTEL_WAKEREF_DEF' is returned, the function returns 'NULL' .

Signed-off-by: Ingyu Jang <ingyujang25 at gmail.com>
---
 drivers/gpu/drm/i915/gt/intel_ggtt.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/gt/intel_ggtt.c b/drivers/gpu/drm/i915/gt/intel_ggtt.c
index d60a6ca0cae5..8d22d8f2243d 100644
--- a/drivers/gpu/drm/i915/gt/intel_ggtt.c
+++ b/drivers/gpu/drm/i915/gt/intel_ggtt.c
@@ -311,7 +311,7 @@ static struct intel_context *gen8_ggtt_bind_get_ce(struct i915_ggtt *ggtt, intel
 	 * doing rpm_resume().
 	 */
 	*wakeref = intel_gt_pm_get_if_awake(gt);
-	if (!*wakeref)
+	if (!*wakeref || *wakeref == INTEL_WAKEREF_DEF)
 		return NULL;
 
 	intel_engine_pm_get(ce->engine);
-- 
2.34.1