drm/amdgpu: do necessary NULL check

Signed-off-by: Jammy Zhou <Jammy.Zhou@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>

1 files changed, 5 insertions, 2 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_sync.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_sync.c
index 855d56ac7115..21accbdd0a1a 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_sync.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_sync.c
@@ -101,6 +101,9 @@ int amdgpu_sync_resv(struct amdgpu_device *adev,
         unsigned i;
         int r = 0;
 
+        if (resv == NULL)
+                return -EINVAL;
+
         /* always sync to the exclusive fence */
         f = reservation_object_get_excl(resv);
         fence = f ? to_amdgpu_fence(f) : NULL;
@@ -116,12 +119,12 @@ int amdgpu_sync_resv(struct amdgpu_device *adev,
         for (i = 0; i < flist->shared_count; ++i) {
                 f = rcu_dereference_protected(flist->shared[i],
                                               reservation_object_held(resv));
-                fence = to_amdgpu_fence(f);
+                fence = f ? to_amdgpu_fence(f) : NULL;
                 if (fence && fence->ring->adev == adev) {
                         if (fence->owner != owner ||
                             fence->owner == AMDGPU_FENCE_OWNER_UNDEFINED)
                                 amdgpu_sync_fence(sync, fence);
-                } else {
+                } else if (f) {
                         r = fence_wait(f, true);
                         if (r)
                                 break;