scsi: smartpqi: Avoid crashing kernel for controller issues

Eliminate kernel panics when getting invalid responses from controller.
Take controller offline instead of causing kernel panics.

Link: https://lore.kernel.org/r/159622929306.30579.16523318707596752828.stgit@brunhilda
Reviewed-by: Scott Teel <scott.teel@microsemi.com>
Reviewed-by: Scott Benesh <scott.benesh@microsemi.com>
Reviewed-by: Prasad Munirathnam <Prasad.Munirathnam@microsemi.com>
Reviewed-by: Martin Wilck <mwilck@suse.com>
Signed-off-by: Kevin Barnett <kevin.barnett@microsemi.com>
Signed-off-by: Don Brace <don.brace@microsemi.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/smartpqi/smartpqi.h b/drivers/scsi/smartpqi/smartpqi.h
index c2382ee..631306d 100644 (file)
--- a/drivers/scsi/smartpqi/smartpqi.h
+++ b/drivers/scsi/smartpqi/smartpqi.h
@@ -359,7 +359,7 @@ struct pqi_event_response {
        struct pqi_iu_header header;
        u8      event_type;
        u8      reserved2 : 7;
-       u8      request_acknowlege : 1;
+       u8      request_acknowledge : 1;
        __le16  event_id;
        __le32  additional_event_id;
        union {

diff --git a/drivers/scsi/smartpqi/smartpqi_init.c b/drivers/scsi/smartpqi/smartpqi_init.c
index 8f37b98..2d4a9aa 100644 (file)
--- a/drivers/scsi/smartpqi/smartpqi_init.c
+++ b/drivers/scsi/smartpqi/smartpqi_init.c
@@ -542,8 +542,7 @@ static int pqi_build_raid_path_request(struct pqi_ctrl_info *ctrl_info,
                put_unaligned_be16(cdb_length, &cdb[7]);
                break;
        default:
-               dev_err(&ctrl_info->pci_dev->dev, "unknown command 0x%c\n",
-                       cmd);
+               dev_err(&ctrl_info->pci_dev->dev, "unknown command 0x%c\n", cmd);
                break;
        }
 
@@ -2461,7 +2460,6 @@ static int pqi_raid_bypass_submit_scsi_cmd(struct pqi_ctrl_info *ctrl_info,
                offload_to_mirror =
                        (offload_to_mirror >= layout_map_count - 1) ?
                                0 : offload_to_mirror + 1;
-               WARN_ON(offload_to_mirror >= layout_map_count);
                device->offload_to_mirror = offload_to_mirror;
                /*
                 * Avoid direct use of device->offload_to_mirror within this
@@ -2914,10 +2912,14 @@ static int pqi_interpret_task_management_response(
        return rc;
 }
 
-static unsigned int pqi_process_io_intr(struct pqi_ctrl_info *ctrl_info,
-       struct pqi_queue_group *queue_group)
+static inline void pqi_invalid_response(struct pqi_ctrl_info *ctrl_info)
+{
+       pqi_take_ctrl_offline(ctrl_info);
+}
+
+static int pqi_process_io_intr(struct pqi_ctrl_info *ctrl_info, struct pqi_queue_group *queue_group)
 {
-       unsigned int num_responses;
+       int num_responses;
        pqi_index_t oq_pi;
        pqi_index_t oq_ci;
        struct pqi_io_request *io_request;
@@ -2929,6 +2931,13 @@ static unsigned int pqi_process_io_intr(struct pqi_ctrl_info *ctrl_info,
 
        while (1) {
                oq_pi = readl(queue_group->oq_pi);
+               if (oq_pi >= ctrl_info->num_elements_per_oq) {
+                       pqi_invalid_response(ctrl_info);
+                       dev_err(&ctrl_info->pci_dev->dev,
+                               "I/O interrupt: producer index (%u) out of range (0-%u): consumer index: %u\n",
+                               oq_pi, ctrl_info->num_elements_per_oq - 1, oq_ci);
+                       return -1;
+               }
                if (oq_pi == oq_ci)
                        break;
 
@@ -2937,10 +2946,22 @@ static unsigned int pqi_process_io_intr(struct pqi_ctrl_info *ctrl_info,
                        (oq_ci * PQI_OPERATIONAL_OQ_ELEMENT_LENGTH);
 
                request_id = get_unaligned_le16(&response->request_id);
-               WARN_ON(request_id >= ctrl_info->max_io_slots);
+               if (request_id >= ctrl_info->max_io_slots) {
+                       pqi_invalid_response(ctrl_info);
+                       dev_err(&ctrl_info->pci_dev->dev,
+                               "request ID in response (%u) out of range (0-%u): producer index: %u  consumer index: %u\n",
+                               request_id, ctrl_info->max_io_slots - 1, oq_pi, oq_ci);
+                       return -1;
+               }
 
                io_request = &ctrl_info->io_request_pool[request_id];
-               WARN_ON(atomic_read(&io_request->refcount) == 0);
+               if (atomic_read(&io_request->refcount) == 0) {
+                       pqi_invalid_response(ctrl_info);
+                       dev_err(&ctrl_info->pci_dev->dev,
+                               "request ID in response (%u) does not match an outstanding I/O request: producer index: %u  consumer index: %u\n",
+                               request_id, oq_pi, oq_ci);
+                       return -1;
+               }
 
                switch (response->header.iu_type) {
                case PQI_RESPONSE_IU_RAID_PATH_IO_SUCCESS:
@@ -2970,24 +2991,22 @@ static unsigned int pqi_process_io_intr(struct pqi_ctrl_info *ctrl_info,
                        io_request->error_info = ctrl_info->error_buffer +
                                (get_unaligned_le16(&response->error_index) *
                                PQI_ERROR_BUFFER_ELEMENT_LENGTH);
-                       pqi_process_io_error(response->header.iu_type,
-                               io_request);
+                       pqi_process_io_error(response->header.iu_type, io_request);
                        break;
                default:
+                       pqi_invalid_response(ctrl_info);
                        dev_err(&ctrl_info->pci_dev->dev,
-                               "unexpected IU type: 0x%x\n",
-                               response->header.iu_type);
-                       break;
+                               "unexpected IU type: 0x%x: producer index: %u  consumer index: %u\n",
+                               response->header.iu_type, oq_pi, oq_ci);
+                       return -1;
                }
 
-               io_request->io_complete_callback(io_request,
-                       io_request->context);
+               io_request->io_complete_callback(io_request, io_request->context);
 
                /*
                 * Note that the I/O request structure CANNOT BE TOUCHED after
                 * returning from the I/O completion callback!
                 */
-
                oq_ci = (oq_ci + 1) % ctrl_info->num_elements_per_oq;
        }
 
@@ -3300,9 +3319,9 @@ static void pqi_ofa_capture_event_payload(struct pqi_event *event,
        }
 }
 
-static unsigned int pqi_process_event_intr(struct pqi_ctrl_info *ctrl_info)
+static int pqi_process_event_intr(struct pqi_ctrl_info *ctrl_info)
 {
-       unsigned int num_events;
+       int num_events;
        pqi_index_t oq_pi;
        pqi_index_t oq_ci;
        struct pqi_event_queue *event_queue;
@@ -3316,26 +3335,31 @@ static unsigned int pqi_process_event_intr(struct pqi_ctrl_info *ctrl_info)
 
        while (1) {
                oq_pi = readl(event_queue->oq_pi);
+               if (oq_pi >= PQI_NUM_EVENT_QUEUE_ELEMENTS) {
+                       pqi_invalid_response(ctrl_info);
+                       dev_err(&ctrl_info->pci_dev->dev,
+                               "event interrupt: producer index (%u) out of range (0-%u): consumer index: %u\n",
+                               oq_pi, PQI_NUM_EVENT_QUEUE_ELEMENTS - 1, oq_ci);
+                       return -1;
+               }
+
                if (oq_pi == oq_ci)
                        break;
 
                num_events++;
-               response = event_queue->oq_element_array +
-                       (oq_ci * PQI_EVENT_OQ_ELEMENT_LENGTH);
+               response = event_queue->oq_element_array + (oq_ci * PQI_EVENT_OQ_ELEMENT_LENGTH);
 
                event_index =
                        pqi_event_type_to_event_index(response->event_type);
 
-               if (event_index >= 0) {
-                       if (response->request_acknowlege) {
-                               event = &ctrl_info->events[event_index];
-                               event->pending = true;
-                               event->event_type = response->event_type;
-                               event->event_id = response->event_id;
-                               event->additional_event_id =
-                                       response->additional_event_id;
+               if (event_index >= 0 && response->request_acknowledge) {
+                       event = &ctrl_info->events[event_index];
+                       event->pending = true;
+                       event->event_type = response->event_type;
+                       event->event_id = response->event_id;
+                       event->additional_event_id = response->additional_event_id;
+                       if (event->event_type == PQI_EVENT_TYPE_OFA)
                                pqi_ofa_capture_event_payload(event, response);
-                       }
                }
 
                oq_ci = (oq_ci + 1) % PQI_NUM_EVENT_QUEUE_ELEMENTS;
@@ -3450,7 +3474,8 @@ static irqreturn_t pqi_irq_handler(int irq, void *data)
 {
        struct pqi_ctrl_info *ctrl_info;
        struct pqi_queue_group *queue_group;
-       unsigned int num_responses_handled;
+       int num_io_responses_handled;
+       int num_events_handled;
 
        queue_group = data;
        ctrl_info = queue_group->ctrl_info;
@@ -3458,17 +3483,25 @@ static irqreturn_t pqi_irq_handler(int irq, void *data)
        if (!pqi_is_valid_irq(ctrl_info))
                return IRQ_NONE;
 
-       num_responses_handled = pqi_process_io_intr(ctrl_info, queue_group);
+       num_io_responses_handled = pqi_process_io_intr(ctrl_info, queue_group);
+       if (num_io_responses_handled < 0)
+               goto out;
 
-       if (irq == ctrl_info->event_irq)
-               num_responses_handled += pqi_process_event_intr(ctrl_info);
+       if (irq == ctrl_info->event_irq) {
+               num_events_handled = pqi_process_event_intr(ctrl_info);
+               if (num_events_handled < 0)
+                       goto out;
+       } else {
+               num_events_handled = 0;
+       }
 
-       if (num_responses_handled)
+       if (num_io_responses_handled + num_events_handled > 0)
                atomic_inc(&ctrl_info->num_interrupts);
 
        pqi_start_io(ctrl_info, queue_group, RAID_PATH, NULL);
        pqi_start_io(ctrl_info, queue_group, AIO_PATH, NULL);
 
+out:
        return IRQ_HANDLED;
 }