drm/amdkfd: destroy dbgmgr in notifier release

amdkfd need to destroy the debug manager in case amdkfd's notifier
function is called before the unbind function, because in that case,
the unbind function will exit without destroying debug manager.
Signed-off-by: NOded Gabbay <oded.gabbay@gmail.com>
CC: Stable <stable@vger.kernel.org>

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

@@ -242,13 +242,19 @@ static void kfd_process_notifier_release(struct mmu_notifier *mn,
 	pqm_uninit(&p->pqm);
 
 	/* Iterate over all process device data structure and check
-	 * if we should reset all wavefronts */
-	list_for_each_entry(pdd, &p->per_device_data, per_device_list)
+	 * if we should delete debug managers and reset all wavefronts
+	 */
+	list_for_each_entry(pdd, &p->per_device_data, per_device_list) {
+		if ((pdd->dev->dbgmgr) &&
+				(pdd->dev->dbgmgr->pasid == p->pasid))
+			kfd_dbgmgr_destroy(pdd->dev->dbgmgr);
+
 		if (pdd->reset_wavefronts) {
 			pr_warn("amdkfd: Resetting all wave fronts\n");
 			dbgdev_wave_reset_wavefronts(pdd->dev, p);
 			pdd->reset_wavefronts = false;
 		}
+	}
 
 	mutex_unlock(&p->mutex);