From b95b9452aacf80659ea67bf0948cbfa7e28e5e0b Mon Sep 17 00:00:00 2001 From: Sawan Chandak Date: Wed, 24 May 2017 18:06:20 -0700 Subject: [PATCH] scsi: qla2xxx: Fix crash due to mismatch mumber of Q-pair creation for Multi queue when driver is loaded with Multi Queue enabled, it was noticed that there was one less queue pair created. Following message would indicate this: "No resources to create additional q pair." The result of one less queue pair means that system can crash, if the block mq layer thinks there is an extra hardware queue available, and the driver will use a NULL ptr qpair in that instance. Following stack trace is seen in one of the crash: irq_create_affinity_masks+0x98/0x530 irq_create_affinity_masks+0x98/0x530 __pci_enable_msix+0x321/0x4e0 mutex_lock+0x12/0x40 pci_alloc_irq_vectors_affinity+0xb5/0x140 qla24xx_enable_msix+0x79/0x530 [qla2xxx] qla2x00_request_irqs+0x61/0x2d0 [qla2xxx] qla2x00_probe_one+0xc73/0x2390 [qla2xxx] ida_simple_get+0x98/0x100 kernfs_next_descendant_post+0x40/0x50 local_pci_probe+0x45/0xa0 pci_device_probe+0xfc/0x140 driver_probe_device+0x2c5/0x470 __driver_attach+0xdd/0xe0 driver_probe_device+0x470/0x470 bus_for_each_dev+0x6c/0xc0 driver_attach+0x1e/0x20 bus_add_driver+0x45/0x270 driver_register+0x60/0xe0 __pci_register_driver+0x4c/0x50 qla2x00_module_init+0x1ce/0x21e [qla2xxx] Cc: # v4.10+ Signed-off-by: Sawan Chandak Signed-off-by: Himanshu Madhani Signed-off-by: Martin K. Petersen --- drivers/scsi/qla2xxx/qla_def.h | 1 + drivers/scsi/qla2xxx/qla_init.c | 5 ++++- 2 files changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/scsi/qla2xxx/qla_def.h b/drivers/scsi/qla2xxx/qla_def.h index ae119018dfaa..eddbc1218a39 100644 --- a/drivers/scsi/qla2xxx/qla_def.h +++ b/drivers/scsi/qla2xxx/qla_def.h @@ -3425,6 +3425,7 @@ struct qla_hw_data { uint8_t max_req_queues; uint8_t max_rsp_queues; uint8_t max_qpairs; + uint8_t num_qpairs; struct qla_qpair *base_qpair; struct qla_npiv_entry *npiv_info; uint16_t nvram_npiv_size; diff --git a/drivers/scsi/qla2xxx/qla_init.c b/drivers/scsi/qla2xxx/qla_init.c index 034743309ada..0391fc317003 100644 --- a/drivers/scsi/qla2xxx/qla_init.c +++ b/drivers/scsi/qla2xxx/qla_init.c @@ -7543,12 +7543,13 @@ struct qla_qpair *qla2xxx_create_qpair(struct scsi_qla_host *vha, int qos, int v /* Assign available que pair id */ mutex_lock(&ha->mq_lock); qpair_id = find_first_zero_bit(ha->qpair_qid_map, ha->max_qpairs); - if (qpair_id >= ha->max_qpairs) { + if (ha->num_qpairs >= ha->max_qpairs) { mutex_unlock(&ha->mq_lock); ql_log(ql_log_warn, vha, 0x0183, "No resources to create additional q pair.\n"); goto fail_qid_map; } + ha->num_qpairs++; set_bit(qpair_id, ha->qpair_qid_map); ha->queue_pair_map[qpair_id] = qpair; qpair->id = qpair_id; @@ -7635,6 +7636,7 @@ fail_rsp: fail_msix: ha->queue_pair_map[qpair_id] = NULL; clear_bit(qpair_id, ha->qpair_qid_map); + ha->num_qpairs--; mutex_unlock(&ha->mq_lock); fail_qid_map: kfree(qpair); @@ -7660,6 +7662,7 @@ int qla2xxx_delete_qpair(struct scsi_qla_host *vha, struct qla_qpair *qpair) mutex_lock(&ha->mq_lock); ha->queue_pair_map[qpair->id] = NULL; clear_bit(qpair->id, ha->qpair_qid_map); + ha->num_qpairs--; list_del(&qpair->qp_list_elem); if (list_empty(&vha->qp_list)) vha->flags.qpairs_available = 0; -- 2.11.0