scsi: smartpqi: fix rare system hang during LUN reset

Correct a rare case where in a LUN reset occurs on a device and I/O
requests for other devices persist in the driver's internal request queue.

Part of a LUN reset involves waiting for our internal request queue to
empty before proceeding. The internal request queue contains requests not
yet sent down to the controller.

We were clearing the requests queued for the LUN undergoing a reset, but
not all of the queued requests. Causing a hang.

For all requests in our internal request queue:

   Complete requests with DID_RESET for queued requests for the device
   undergoing a reset.

   Complete requests with DID_REQUEUE for all other queued requests.

Reviewed-by: Scott Benesh <scott.benesh@microchip.com>
Reviewed-by: Scott Teel <scott.teel@microchip.com>
Reviewed-by: Mike McGowen <mike.mcgowen@microchip.com>
Signed-off-by: Murthy Bhat <Murthy.Bhat@microchip.com>
Signed-off-by: Don Brace <don.brace@microchip.com>
Link: https://lore.kernel.org/r/20240827185501.692804-6-don.brace@microchip.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/smartpqi/smartpqi_init.c b/drivers/scsi/smartpqi/smartpqi_init.c
index 46bef2cf95c4bae52cfab1df29603f4109d7ebdd..d1d117d5d08dcbbdc2c822aec1f14425ff7e4670 100644 (file)
--- a/drivers/scsi/smartpqi/smartpqi_init.c
+++ b/drivers/scsi/smartpqi/smartpqi_init.c
@@ -6200,14 +6200,12 @@ static void pqi_fail_io_queued_for_device(struct pqi_ctrl_info *ctrl_info,
                                        continue;
 
                                scsi_device = scmd->device->hostdata;
-                               if (scsi_device != device)
-                                       continue;
-
-                               if ((u8)scmd->device->lun != lun)
-                                       continue;
 
                                list_del(&io_request->request_list_entry);
-                               set_host_byte(scmd, DID_RESET);
+                               if (scsi_device == device && (u8)scmd->device->lun == lun)
+                                       set_host_byte(scmd, DID_RESET);
+                               else
+                                       set_host_byte(scmd, DID_REQUEUE);
                                pqi_free_io_request(io_request);
                                scsi_dma_unmap(scmd);
                                pqi_scsi_done(scmd);