drm/amd/amdkfd: Fix kernel panic when reset failed and been triggered…

… again

[ Upstream commit 2cf49e0 ]

In SRIOV configuration, the reset may failed to bring asic back to normal but stop cpsch
already been called, the start_cpsch will not be called since there is no resume in this
case.  When reset been triggered again, driver should avoid to do uninitialization again.

Signed-off-by: shaoyunl <shaoyun.liu@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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

@@ -1225,6 +1225,11 @@ static int stop_cpsch(struct device_queue_manager *dqm)
 	bool hanging;
 
 	dqm_lock(dqm);
+	if (!dqm->sched_running) {
+		dqm_unlock(dqm);
+		return 0;
+	}
+
 	if (!dqm->is_hws_hang)
 		unmap_queues_cpsch(dqm, KFD_UNMAP_QUEUES_FILTER_ALL_QUEUES, 0);
 	hanging = dqm->is_hws_hang || dqm->is_resetting;