On Aug 5, 2021, at 5:20 AM, Nilesh Javali [off-list ref] wrote:

From: Saurav Kashyap <skashyap@marvell.com>

The MSI-X and MSI calls fails in kdump kernel, because of this
qla2xxx_create_qpair fails leading to .create_queue callback failure.
The fix is to return existing qpair instead of allocating new one and
allocate single hw queue.

[   19.975838] qla2xxx [0000:d8:00.1]-00c7:11: MSI-X: Failed to enable support,
giving   up -- 16/-28.
[   19.984885] qla2xxx [0000:d8:00.1]-0037:11: Falling back-to MSI mode --
ret=-28.
[   19.992278] qla2xxx [0000:d8:00.1]-0039:11: Falling back-to INTa mode --
ret=-28.
..
..
..
[   21.141518] qla2xxx [0000:d8:00.0]-2104:2: qla_nvme_alloc_queue: handle
00000000e7ee499d, idx =1, qsize 32
[   21.151166] qla2xxx [0000:d8:00.0]-0181:2: FW/Driver is not multi-queue capable.
[   21.158558] qla2xxx [0000:d8:00.0]-2122:2: Failed to allocate qpair
[   21.164824] nvme nvme0: NVME-FC{0}: reset: Reconnect attempt failed (-22)
[   21.171612] nvme nvme0: NVME-FC{0}: Reconnect attempt in 2 seconds

Signed-off-by: Saurav Kashyap <skashyap@marvell.com>
Signed-off-by: Nilesh Javali <njavali@marvell.com>
---
drivers/scsi/qla2xxx/qla_def.h  |  1 -
drivers/scsi/qla2xxx/qla_isr.c  |  2 ++
drivers/scsi/qla2xxx/qla_nvme.c | 40 +++++++++++++++------------------
3 files changed, 20 insertions(+), 23 deletions(-)

diff --git a/drivers/scsi/qla2xxx/qla_def.h b/drivers/scsi/qla2xxx/qla_def.h
index 60702d066ed9..55175e8a0749 100644
--- a/drivers/scsi/qla2xxx/qla_def.h
+++ b/drivers/scsi/qla2xxx/qla_def.h

@@ -4022,7 +4022,6 @@ struct qla_hw_data {

				/* Enabled in Driver */
		uint32_t	scm_enabled:1;
		uint32_t	edif_enabled:1;
-		uint32_t	max_req_queue_warned:1;
		uint32_t	plogi_template_valid:1;
		uint32_t	port_isolated:1;
	} flags;

diff --git a/drivers/scsi/qla2xxx/qla_isr.c b/drivers/scsi/qla2xxx/qla_isr.c
index b0b5af21781a..ba4a5bf5600a 100644
--- a/drivers/scsi/qla2xxx/qla_isr.c
+++ b/drivers/scsi/qla2xxx/qla_isr.c

@@ -4508,6 +4508,8 @@ qla2x00_request_irqs(struct qla_hw_data *ha, struct rsp_que *rsp)

		ql_dbg(ql_dbg_init, vha, 0x0125,
		    "INTa mode: Enabled.\n");
		ha->flags.mr_intr_valid = 1;
+		/* Set max_qpair to 0, as MSI-X and MSI in not enabled */
+		ha->max_qpairs = 0;
	}

clear_risc_ints:

diff --git a/drivers/scsi/qla2xxx/qla_nvme.c b/drivers/scsi/qla2xxx/qla_nvme.c
index 6f3c0a506509..94e350ef3028 100644
--- a/drivers/scsi/qla2xxx/qla_nvme.c
+++ b/drivers/scsi/qla2xxx/qla_nvme.c

@@ -108,19 +108,24 @@ static int qla_nvme_alloc_queue(struct nvme_fc_local_port *lport,

		return -EINVAL;
	}

-	if (ha->queue_pair_map[qidx]) {
-		*handle = ha->queue_pair_map[qidx];
-		ql_log(ql_log_info, vha, 0x2121,
-		    "Returning existing qpair of %px for idx=%x\n",
-		    *handle, qidx);
-		return 0;
-	}
+	/* Use base qpair if max_qpairs is 0 */
+	if (!ha->max_qpairs) {
+		qpair = ha->base_qpair;
+	} else {
+		if (ha->queue_pair_map[qidx]) {
+			*handle = ha->queue_pair_map[qidx];
+			ql_log(ql_log_info, vha, 0x2121,
+			       "Returning existing qpair of %px for idx=%x\n",
+			       *handle, qidx);
+			return 0;
+		}

-	qpair = qla2xxx_create_qpair(vha, 5, vha->vp_idx, true);
-	if (qpair == NULL) {
-		ql_log(ql_log_warn, vha, 0x2122,
-		    "Failed to allocate qpair\n");
-		return -EINVAL;
+		qpair = qla2xxx_create_qpair(vha, 5, vha->vp_idx, true);
+		if (!qpair) {
+			ql_log(ql_log_warn, vha, 0x2122,
+			       "Failed to allocate qpair\n");
+			return -EINVAL;
+		}
	}
	*handle = qpair;

@@ -731,18 +736,9 @@ int qla_nvme_register_hba(struct scsi_qla_host *vha)

	WARN_ON(vha->nvme_local_port);

-	if (ha->max_req_queues < 3) {
-		if (!ha->flags.max_req_queue_warned)
-			ql_log(ql_log_info, vha, 0x2120,
-			       "%s: Disabling FC-NVME due to lack of free queue pairs (%d).\n",
-			       __func__, ha->max_req_queues);
-		ha->flags.max_req_queue_warned = 1;
-		return ret;
-	}
-
	qla_nvme_fc_transport.max_hw_queues =
	    min((uint8_t)(qla_nvme_fc_transport.max_hw_queues),
-		(uint8_t)(ha->max_req_queues - 2));
+		(uint8_t)(ha->max_qpairs ? ha->max_qpairs : 1));

	pinfo.node_name = wwn_to_u64(vha->node_name);
	pinfo.port_name = wwn_to_u64(vha->port_name);
-- 
2.19.0.rc0