[PATCH 2/2] drm/xe/ufence: Warn if mmget_not_zero() fails

[Nirmoy Das <nirmoy.das@intel.com>]

This shouldn't happen but seen this while debugging ufence timeout
issue time to time so log it to isolate this particular case.

Link: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/1630
Cc: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: Nirmoy Das <nirmoy.das@intel.com>
Reviewed-by: Francois Dugast <francois.dugast@intel.com>
---
 drivers/gpu/drm/xe/xe_sync.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/xe/xe_sync.c b/drivers/gpu/drm/xe/xe_sync.c
index 2e72c06fd40d..22f72df36ab2 100644
--- a/drivers/gpu/drm/xe/xe_sync.c
+++ b/drivers/gpu/drm/xe/xe_sync.c
@@ -83,6 +83,8 @@ static void user_fence_worker(struct work_struct *w)
 			XE_WARN_ON("Copy to user failed");
 		kthread_unuse_mm(ufence->mm);
 		mmput(ufence->mm);
+	} else {
+		XE_WARN_ON("mmget_not_zero() failed");
 	}
 
 	wake_up_all(&ufence->xe->ufence_wq);
-- 
2.46.0