scsi: qla2xxx: Flush mailbox commands on chip reset

Fix race condition between Interrupt thread and Chip reset thread in trying
to flush the same mailbox. With the race condition, the "ha->mbx_intr_comp"
will get an extra complete() call. The extra complete call create erroneous
mailbox timeout condition when the next mailbox is sent where the mailbox
call does not wait for interrupt to arrive. Instead, it advances without
waiting.

Add lock protection around the check for mailbox completion.

Cc: stable@vger.kernel.org
Fixes: b2000805a975 ("scsi: qla2xxx: Flush mailbox commands on chip reset")
Signed-off-by: Quinn Tran <quinn.tran@marvell.com>
Signed-off-by: Nilesh Javali <njavali@marvell.com>
Link: https://lore.kernel.org/r/20230821130045.34850-3-njavali@marvell.com
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/qla2xxx/qla_def.h b/drivers/scsi/qla2xxx/qla_def.h
index 2007d5b..f1cf921 100644 (file)
--- a/drivers/scsi/qla2xxx/qla_def.h
+++ b/drivers/scsi/qla2xxx/qla_def.h
@@ -4418,7 +4418,6 @@ struct qla_hw_data {
        uint8_t         aen_mbx_count;
        atomic_t        num_pend_mbx_stage1;
        atomic_t        num_pend_mbx_stage2;
-       atomic_t        num_pend_mbx_stage3;
        uint16_t        frame_payload_size;
 
        uint32_t        login_retry_count;

diff --git a/drivers/scsi/qla2xxx/qla_init.c b/drivers/scsi/qla2xxx/qla_init.c
index 2764495..d38b77a 100644 (file)
--- a/drivers/scsi/qla2xxx/qla_init.c
+++ b/drivers/scsi/qla2xxx/qla_init.c
@@ -7391,14 +7391,15 @@ qla2x00_abort_isp_cleanup(scsi_qla_host_t *vha)
        }
 
        /* purge MBox commands */
-       if (atomic_read(&ha->num_pend_mbx_stage3)) {
+       spin_lock_irqsave(&ha->hardware_lock, flags);
+       if (test_bit(MBX_INTR_WAIT, &ha->mbx_cmd_flags)) {
                clear_bit(MBX_INTR_WAIT, &ha->mbx_cmd_flags);
                complete(&ha->mbx_intr_comp);
        }
+       spin_unlock_irqrestore(&ha->hardware_lock, flags);
 
        i = 0;
-       while (atomic_read(&ha->num_pend_mbx_stage3) ||
-           atomic_read(&ha->num_pend_mbx_stage2) ||
+       while (atomic_read(&ha->num_pend_mbx_stage2) ||
            atomic_read(&ha->num_pend_mbx_stage1)) {
                msleep(20);
                i++;

diff --git a/drivers/scsi/qla2xxx/qla_mbx.c b/drivers/scsi/qla2xxx/qla_mbx.c
index b05f930..21ec32b 100644 (file)
--- a/drivers/scsi/qla2xxx/qla_mbx.c
+++ b/drivers/scsi/qla2xxx/qla_mbx.c
@@ -273,7 +273,6 @@ qla2x00_mailbox_command(scsi_qla_host_t *vha, mbx_cmd_t *mcp)
                spin_unlock_irqrestore(&ha->hardware_lock, flags);
 
                wait_time = jiffies;
-               atomic_inc(&ha->num_pend_mbx_stage3);
                if (!wait_for_completion_timeout(&ha->mbx_intr_comp,
                    mcp->tov * HZ)) {
                        ql_dbg(ql_dbg_mbx, vha, 0x117a,
@@ -290,7 +289,6 @@ qla2x00_mailbox_command(scsi_qla_host_t *vha, mbx_cmd_t *mcp)
                                spin_unlock_irqrestore(&ha->hardware_lock,
                                    flags);
                                atomic_dec(&ha->num_pend_mbx_stage2);
-                               atomic_dec(&ha->num_pend_mbx_stage3);
                                rval = QLA_ABORTED;
                                goto premature_exit;
                        }
@@ -302,11 +300,9 @@ qla2x00_mailbox_command(scsi_qla_host_t *vha, mbx_cmd_t *mcp)
                        ha->flags.mbox_busy = 0;
                        spin_unlock_irqrestore(&ha->hardware_lock, flags);
                        atomic_dec(&ha->num_pend_mbx_stage2);
-                       atomic_dec(&ha->num_pend_mbx_stage3);
                        rval = QLA_ABORTED;
                        goto premature_exit;
                }
-               atomic_dec(&ha->num_pend_mbx_stage3);
 
                if (time_after(jiffies, wait_time + 5 * HZ))
                        ql_log(ql_log_warn, vha, 0x1015, "cmd=0x%x, waited %d msecs\n",

diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c
index aa49248..e380634 100644 (file)
--- a/drivers/scsi/qla2xxx/qla_os.c
+++ b/drivers/scsi/qla2xxx/qla_os.c
@@ -3008,7 +3008,6 @@ qla2x00_probe_one(struct pci_dev *pdev, const struct pci_device_id *id)
        ha->max_exchg = FW_MAX_EXCHANGES_CNT;
        atomic_set(&ha->num_pend_mbx_stage1, 0);
        atomic_set(&ha->num_pend_mbx_stage2, 0);
-       atomic_set(&ha->num_pend_mbx_stage3, 0);
        atomic_set(&ha->zio_threshold, DEFAULT_ZIO_THRESHOLD);
        ha->last_zio_threshold = DEFAULT_ZIO_THRESHOLD;
        INIT_LIST_HEAD(&ha->tmf_pending);