[PATCH 2/5] drm/amd/display: Fix null pointer derference in amdgpu_dm_fini()

[Mario Limonciello]

Some error cleaning paths call amdgpu_dm_fini() but may not have
initialized `adev->dm.delayed_hpd_wq`. Catch this and avoid
destroying the workqueue.

Signed-off-by: Mario Limonciello <mario.limoncie...@amd.com>
---
 drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c 
b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 94f1651422da1..5fd3d36964369 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -2219,8 +2219,10 @@ static void amdgpu_dm_fini(struct amdgpu_device *adev)
                if (dc_enable_dmub_notifications(adev->dm.dc)) {
                        kfree(adev->dm.dmub_notify);
                        adev->dm.dmub_notify = NULL;
-                       destroy_workqueue(adev->dm.delayed_hpd_wq);
-                       adev->dm.delayed_hpd_wq = NULL;
+                       if (adev->dm.delayed_hpd_wq) {
+                               destroy_workqueue(adev->dm.delayed_hpd_wq);
+                               adev->dm.delayed_hpd_wq = NULL;
+                       }
                }
        }
 
-- 
2.43.0