scsi: mpi3mr: Driver unload crashes host when enhanced logging is enabled

Prevent driver from trying to dereference a NULL pointer in a debug print
while removing a device during driver unload.

Signed-off-by: Ranjan Kumar <[email protected]>
Signed-off-by: Sreekanth Reddy <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Martin K. Petersen <[email protected]>

Author: Ranjan Kumar

drivers/scsi/mpi3mr/mpi3mr_transport.c

@@ -1552,7 +1552,8 @@ static void mpi3mr_sas_port_remove(struct mpi3mr_ioc *mrioc, u64 sas_address,
 
 	list_for_each_entry_safe(mr_sas_phy, next_phy,
 	    &mr_sas_port->phy_list, port_siblings) {
-		if ((mrioc->logging_level & MPI3_DEBUG_TRANSPORT_INFO))
+		if ((!mrioc->stop_drv_processing) &&
+		    (mrioc->logging_level & MPI3_DEBUG_TRANSPORT_INFO))
 			dev_info(&mr_sas_port->port->dev,
 			    "remove: sas_address(0x%016llx), phy(%d)\n",
 			    (unsigned long long)