drm/amdkfd: fix sysfs kobj leak

3 cases of kobj leak, which causes memory leak:

kobj_type must have release() method to free memory from release
callback. Don't need NULL default_attrs to init kobj.

sysfs files created under kobj_status should be removed with kobj_status
as parent kobject.

Remove queue sysfs files when releasing queue from process MMU notifier
release callback.
Signed-off-by: Philip Yang <Philip.Yang@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdkfd/kfd_process.c

@@ -451,13 +451,9 @@ static const struct sysfs_ops procfs_stats_ops = {
 	.show = kfd_procfs_stats_show,
 };
 
-static struct attribute *procfs_stats_attrs[] = {
-	NULL
-};
-
 static struct kobj_type procfs_stats_type = {
 	.sysfs_ops = &procfs_stats_ops,
-	.default_attrs = procfs_stats_attrs,
+	.release = kfd_procfs_kobj_release,
 };
 
 int kfd_procfs_add_queue(struct queue *q)
@@ -946,9 +942,11 @@ static void kfd_process_wq_release(struct work_struct *work)
 
 			sysfs_remove_file(p->kobj, &pdd->attr_vram);
 			sysfs_remove_file(p->kobj, &pdd->attr_sdma);
-			sysfs_remove_file(p->kobj, &pdd->attr_evict);
-			if (pdd->dev->kfd2kgd->get_cu_occupancy != NULL)
-				sysfs_remove_file(p->kobj, &pdd->attr_cu_occupancy);
+
+			sysfs_remove_file(pdd->kobj_stats, &pdd->attr_evict);
+			if (pdd->dev->kfd2kgd->get_cu_occupancy)
+				sysfs_remove_file(pdd->kobj_stats,
+						  &pdd->attr_cu_occupancy);
 			kobject_del(pdd->kobj_stats);
 			kobject_put(pdd->kobj_stats);
 			pdd->kobj_stats = NULL;

drivers/gpu/drm/amd/amdkfd/kfd_process_queue_manager.c

@@ -153,6 +153,7 @@ void pqm_uninit(struct process_queue_manager *pqm)
 		if (pqn->q && pqn->q->gws)
 			amdgpu_amdkfd_remove_gws_from_process(pqm->process->kgd_process_info,
 				pqn->q->gws);
+		kfd_procfs_del_queue(pqn->q);
 		uninit_queue(pqn->q);
 		list_del(&pqn->process_queue_list);
 		kfree(pqn);