Commit d8630bb95f46 ('Serialize session deletion by using work_lock') tries
to fixup a deadlock when deleting sessions, but fails to take
into account the locking rules. This patch resolves the situation
by introducing a separate lock for processing the GNLIST response, and
ensures that sess_lock is released before calling
qlt_schedule_sess_delete().
Cc: Himanshu Madhani <himanshu.madhani@xxxxxxxxxx>
Cc: Quinn Tran <quinn.tran@xxxxxxxxxx>
Fixes: d8630bb95f46 ("scsi: qla2xxx: Serialize session deletion by using work_lock")
Signed-off-by: Hannes Reinecke <hare@xxxxxxxx>
---
drivers/scsi/qla2xxx/qla_def.h | 4 ++--
drivers/scsi/qla2xxx/qla_init.c | 24 +++++++++++++++---------
drivers/scsi/qla2xxx/qla_os.c | 7 ++++++-
drivers/scsi/qla2xxx/qla_target.c | 17 ++++++-----------
4 files changed, 29 insertions(+), 23 deletions(-)
diff --git a/drivers/scsi/qla2xxx/qla_def.h b/drivers/scsi/qla2xxx/qla_def.h
index be7d6824581a..3ca4b6a5eddd 100644
--- a/drivers/scsi/qla2xxx/qla_def.h
+++ b/drivers/scsi/qla2xxx/qla_def.h
@@ -261,9 +261,9 @@
struct name_list_extended {
struct get_name_list_extended *l;
dma_addr_t ldma;
- struct list_head fcports; /* protect by sess_list */
+ struct list_head fcports;
+ spinlock_t fcports_lock;
u32 size;
- u8 sent;
};
/*
* Timeout timer counts in seconds
diff --git a/drivers/scsi/qla2xxx/qla_init.c b/drivers/scsi/qla2xxx/qla_init.c
index 590aa904fdef..4dd897c2c2b1 100644
--- a/drivers/scsi/qla2xxx/qla_init.c
+++ b/drivers/scsi/qla2xxx/qla_init.c
@@ -660,8 +660,7 @@ qla24xx_async_gnl_sp_done(void *s, int res)
(loop_id & 0x7fff));
}
- spin_lock_irqsave(&vha->hw->tgt.sess_lock, flags);
- vha->gnl.sent = 0;
+ spin_lock_irqsave(&vha->gnl.fcports_lock, flags);
INIT_LIST_HEAD(&h);
fcport = tf = NULL;
@@ -670,12 +669,16 @@ qla24xx_async_gnl_sp_done(void *s, int res)
list_for_each_entry_safe(fcport, tf, &h, gnl_entry) {
list_del_init(&fcport->gnl_entry);
+ spin_lock(&vha->hw->tgt.sess_lock);
fcport->flags &= ~(FCF_ASYNC_SENT | FCF_ASYNC_ACTIVE);
+ spin_unlock(&vha->hw->tgt.sess_lock);
ea.fcport = fcport;
qla2x00_fcport_event_handler(vha, &ea);
}
+ spin_unlock_irqrestore(&vha->gnl.fcports_lock, flags);
+ spin_lock_irqsave(&vha->hw->tgt.sess_lock, flags);
/* create new fcport if fw has knowledge of new sessions */
for (i = 0; i < n; i++) {
port_id_t id;
@@ -727,18 +730,21 @@ int qla24xx_async_gnl(struct scsi_qla_host *vha, fc_port_t *fcport)
ql_dbg(ql_dbg_disc, vha, 0x20d9,
"Async-gnlist WWPN %8phC \n", fcport->port_name);
- spin_lock_irqsave(&vha->hw->tgt.sess_lock, flags);
+ spin_lock_irqsave(&vha->gnl.fcports_lock, flags);
+ if (!list_empty(&fcport->gnl_entry)) {
+ spin_unlock_irqrestore(&vha->gnl.fcports_lock, flags);
+ rval = QLA_SUCCESS;
+ goto done;
+ }
+
+ spin_lock(&vha->hw->tgt.sess_lock);
fcport->disc_state = DSC_GNL;
fcport->last_rscn_gen = fcport->rscn_gen;
fcport->last_login_gen = fcport->login_gen;
+ spin_unlock(&vha->hw->tgt.sess_lock);
list_add_tail(&fcport->gnl_entry, &vha->gnl.fcports);
- if (vha->gnl.sent) {
- spin_unlock_irqrestore(&vha->hw->tgt.sess_lock, flags);
- return QLA_SUCCESS;
- }
- vha->gnl.sent = 1;
- spin_unlock_irqrestore(&vha->hw->tgt.sess_lock, flags);
+ spin_unlock_irqrestore(&vha->gnl.fcports_lock, flags);
sp = qla2x00_get_sp(vha, fcport, GFP_KERNEL);
if (!sp)
diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c
index 12ee6e02d146..dc2b188fdce1 100644
--- a/drivers/scsi/qla2xxx/qla_os.c
+++ b/drivers/scsi/qla2xxx/qla_os.c
@@ -4575,6 +4575,7 @@ struct scsi_qla_host *qla2x00_create_host(struct scsi_host_template *sht,
spin_lock_init(&vha->work_lock);
spin_lock_init(&vha->cmd_list_lock);
+ spin_lock_init(&vha->gnl.fcports_lock);
init_waitqueue_head(&vha->fcport_waitQ);
init_waitqueue_head(&vha->vref_waitq);
@@ -4875,6 +4876,8 @@ void qla24xx_create_new_sess(struct scsi_qla_host *vha, struct qla_work_evt *e)
}
qlt_plogi_ack_unref(vha, pla);
} else {
+ fc_port_t *dfcp = NULL;
+
spin_lock_irqsave(&vha->hw->tgt.sess_lock, flags);
tfcp = qla2x00_find_fcport_by_nportid(vha,
&e->u.new_sess.id, 1);
@@ -4897,11 +4900,13 @@ void qla24xx_create_new_sess(struct scsi_qla_host *vha, struct qla_work_evt *e)
default:
fcport->login_pause = 1;
tfcp->conflict = fcport;
- qlt_schedule_sess_for_deletion(tfcp);
+ dfcp = tfcp;
break;
}
}
spin_unlock_irqrestore(&vha->hw->tgt.sess_lock, flags);
+ if (dfcp)
+ qlt_schedule_sess_for_deletion(tfcp);
wwn = wwn_to_u64(fcport->node_name);
diff --git a/drivers/scsi/qla2xxx/qla_target.c b/drivers/scsi/qla2xxx/qla_target.c
index 3735ebd83012..990ef1183f3a 100644
--- a/drivers/scsi/qla2xxx/qla_target.c
+++ b/drivers/scsi/qla2xxx/qla_target.c
@@ -1224,10 +1224,10 @@ static void qla24xx_chk_fcp_state(struct fc_port *sess)
}
}
-/* ha->tgt.sess_lock supposed to be held on entry */
void qlt_schedule_sess_for_deletion(struct fc_port *sess)
{
struct qla_tgt *tgt = sess->tgt;
+ struct qla_hw_data *ha = sess->vha->hw;
unsigned long flags;
if (sess->disc_state == DSC_DELETE_PEND)
@@ -1244,16 +1244,16 @@ void qlt_schedule_sess_for_deletion(struct fc_port *sess)
return;
}
+ spin_lock_irqsave(&ha->tgt.sess_lock, flags);
if (sess->deleted == QLA_SESS_DELETED)
sess->logout_on_delete = 0;
- spin_lock_irqsave(&sess->vha->work_lock, flags);
if (sess->deleted == QLA_SESS_DELETION_IN_PROGRESS) {
- spin_unlock_irqrestore(&sess->vha->work_lock, flags);
+ spin_unlock_irqrestore(&ha->tgt.sess_lock, flags);
return;
}
sess->deleted = QLA_SESS_DELETION_IN_PROGRESS;
- spin_unlock_irqrestore(&sess->vha->work_lock, flags);
+ spin_unlock_irqrestore(&ha->tgt.sess_lock, flags);
sess->disc_state = DSC_DELETE_PEND;
@@ -1262,13 +1262,10 @@ void qlt_schedule_sess_for_deletion(struct fc_port *sess)
ql_dbg(ql_dbg_tgt, sess->vha, 0xe001,
"Scheduling sess %p for deletion\n", sess);
- /* use cancel to push work element through before re-queue */
- cancel_work_sync(&sess->del_work);
INIT_WORK(&sess->del_work, qla24xx_delete_sess_fn);
- queue_work(sess->vha->hw->wq, &sess->del_work);
+ WARN_ON(!queue_work(sess->vha->hw->wq, &sess->del_work));
}
-/* ha->tgt.sess_lock supposed to be held on entry */
static void qlt_clear_tgt_db(struct qla_tgt *tgt)
{
struct fc_port *sess;
@@ -1451,8 +1448,8 @@ qlt_fc_port_deleted(struct scsi_qla_host *vha, fc_port_t *fcport, int max_gen)
ql_dbg(ql_dbg_tgt_mgt, vha, 0xf008, "qla_tgt_fc_port_deleted %p", sess);
sess->local = 1;
- qlt_schedule_sess_for_deletion(sess);
spin_unlock_irqrestore(&vha->hw->tgt.sess_lock, flags);
+ qlt_schedule_sess_for_deletion(sess);
}
static inline int test_tgt_sess_count(struct qla_tgt *tgt)
@@ -1512,10 +1509,8 @@ int qlt_stop_phase1(struct qla_tgt *tgt)
* Lock is needed, because we still can get an incoming packet.
*/
mutex_lock(&vha->vha_tgt.tgt_mutex);
- spin_lock_irqsave(&ha->tgt.sess_lock, flags);
tgt->tgt_stop = 1;
qlt_clear_tgt_db(tgt);
- spin_unlock_irqrestore(&ha->tgt.sess_lock, flags);
mutex_unlock(&vha->vha_tgt.tgt_mutex);
mutex_unlock(&qla_tgt_mutex);
--
2.12.3
