[01/10] qla2xxx: Fix deletion race condition

From: Quinn Tran <qutran@marvell.com>

System crash when using debug kernel due
to link list corruption. The cause of the link list corruption
is due to session deletion was allowed to queue up twice.
Here's the internal trace that show the same port was allowed to double
queue for deletion on different cpu.

20808683956 015 qla2xxx [0000:13:00.1]-e801:4: Scheduling sess ffff93ebf9306800 for deletion 50:06:0e:80:12:48:ff:50 fc4_type 1
20808683957 027 qla2xxx [0000:13:00.1]-e801:4: Scheduling sess ffff93ebf9306800 for deletion 50:06:0e:80:12:48:ff:50 fc4_type 1

Move the clearing/setting of deleted flag lock.

Cc: stable@vger.kernel.org
Fixes: 726b85487067 (“qla2xxx: Add framework for async fabric discovery”)
Signed-off-by: Quinn Tran <qutran@marvell.com>
Signed-off-by: Nilesh Javali <njavali@marvell.com>
---
 drivers/scsi/qla2xxx/qla_init.c   | 16 ++++++++++++++--
 drivers/scsi/qla2xxx/qla_target.c | 14 +++++++-------
 2 files changed, 21 insertions(+), 9 deletions(-)

> On Jul 12, 2023, at 2:05 AM, Nilesh Javali <njavali@marvell.com> wrote:
> 
> From: Quinn Tran <qutran@marvell.com>
> 
> System crash when using debug kernel due
> to link list corruption. The cause of the link list corruption
> is due to session deletion was allowed to queue up twice.
> Here's the internal trace that show the same port was allowed to double
> queue for deletion on different cpu.
> 
> 20808683956 015 qla2xxx [0000:13:00.1]-e801:4: Scheduling sess ffff93ebf9306800 for deletion 50:06:0e:80:12:48:ff:50 fc4_type 1
> 20808683957 027 qla2xxx [0000:13:00.1]-e801:4: Scheduling sess ffff93ebf9306800 for deletion 50:06:0e:80:12:48:ff:50 fc4_type 1
> 
> Move the clearing/setting of deleted flag lock.
> 
> Cc: stable@vger.kernel.org
> Fixes: 726b85487067 (“qla2xxx: Add framework for async fabric discovery”)
> Signed-off-by: Quinn Tran <qutran@marvell.com>
> Signed-off-by: Nilesh Javali <njavali@marvell.com>
> ---
> drivers/scsi/qla2xxx/qla_init.c   | 16 ++++++++++++++--
> drivers/scsi/qla2xxx/qla_target.c | 14 +++++++-------
> 2 files changed, 21 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/scsi/qla2xxx/qla_init.c b/drivers/scsi/qla2xxx/qla_init.c
> index b22b0516da29..f8f64ed4de07 100644
> --- a/drivers/scsi/qla2xxx/qla_init.c
> +++ b/drivers/scsi/qla2xxx/qla_init.c
> @@ -508,6 +508,7 @@ static
> void qla24xx_handle_adisc_event(scsi_qla_host_t *vha, struct event_arg *ea)
> {
> struct fc_port *fcport = ea->fcport;
> + unsigned long flags;
> 
> ql_dbg(ql_dbg_disc, vha, 0x20d2,
>    "%s %8phC DS %d LS %d rc %d login %d|%d rscn %d|%d lid %d\n",
> @@ -522,9 +523,15 @@ void qla24xx_handle_adisc_event(scsi_qla_host_t *vha, struct event_arg *ea)
> ql_dbg(ql_dbg_disc, vha, 0x2066,
>    "%s %8phC: adisc fail: post delete\n",
>    __func__, ea->fcport->port_name);
> +
> + spin_lock_irqsave(&vha->work_lock, flags);
> /* deleted = 0 & logout_on_delete = force fw cleanup */
> - fcport->deleted = 0;
> + if (fcport->deleted == QLA_SESS_DELETED)
> + fcport->deleted = 0;
> +
> fcport->logout_on_delete = 1;
> + spin_unlock_irqrestore(&vha->work_lock, flags);
> +
> qlt_schedule_sess_for_deletion(ea->fcport);
> return;
> }
> @@ -1446,7 +1453,6 @@ void __qla24xx_handle_gpdb_event(scsi_qla_host_t *vha, struct event_arg *ea)
> 
> spin_lock_irqsave(&vha->hw->tgt.sess_lock, flags);
> ea->fcport->login_gen++;
> - ea->fcport->deleted = 0;
> ea->fcport->logout_on_delete = 1;
> 
> if (!ea->fcport->login_succ && !IS_SW_RESV_ADDR(ea->fcport->d_id)) {
> @@ -6090,6 +6096,8 @@ qla2x00_reg_remote_port(scsi_qla_host_t *vha, fc_port_t *fcport)
> void
> qla2x00_update_fcport(scsi_qla_host_t *vha, fc_port_t *fcport)
> {
> + unsigned long flags;
> +
> if (IS_SW_RESV_ADDR(fcport->d_id))
> return;
> 
> @@ -6099,7 +6107,11 @@ qla2x00_update_fcport(scsi_qla_host_t *vha, fc_port_t *fcport)
> qla2x00_set_fcport_disc_state(fcport, DSC_UPD_FCPORT);
> fcport->login_retry = vha->hw->login_retry_count;
> fcport->flags &= ~(FCF_LOGIN_NEEDED | FCF_ASYNC_SENT);
> +
> + spin_lock_irqsave(&vha->work_lock, flags);
> fcport->deleted = 0;
> + spin_unlock_irqrestore(&vha->work_lock, flags);
> +
> if (vha->hw->current_topology == ISP_CFG_NL)
> fcport->logout_on_delete = 0;
> else
> diff --git a/drivers/scsi/qla2xxx/qla_target.c b/drivers/scsi/qla2xxx/qla_target.c
> index 5258b07687a9..2b815a9928ea 100644
> --- a/drivers/scsi/qla2xxx/qla_target.c
> +++ b/drivers/scsi/qla2xxx/qla_target.c
> @@ -1068,10 +1068,6 @@ void qlt_free_session_done(struct work_struct *work)
> (struct imm_ntfy_from_isp *)sess->iocb, SRB_NACK_LOGO);
> }
> 
> - spin_lock_irqsave(&vha->work_lock, flags);
> - sess->flags &= ~FCF_ASYNC_SENT;
> - spin_unlock_irqrestore(&vha->work_lock, flags);
> -
> spin_lock_irqsave(&ha->tgt.sess_lock, flags);
> if (sess->se_sess) {
> sess->se_sess = NULL;
> @@ -1081,7 +1077,6 @@ void qlt_free_session_done(struct work_struct *work)
> 
> qla2x00_set_fcport_disc_state(sess, DSC_DELETED);
> sess->fw_login_state = DSC_LS_PORT_UNAVAIL;
> - sess->deleted = QLA_SESS_DELETED;
> 
> if (sess->login_succ && !IS_SW_RESV_ADDR(sess->d_id)) {
> vha->fcport_count--;
> @@ -1133,10 +1128,15 @@ void qlt_free_session_done(struct work_struct *work)
> 
> sess->explicit_logout = 0;
> spin_unlock_irqrestore(&ha->tgt.sess_lock, flags);
> - sess->free_pending = 0;
> 
> qla2x00_dfs_remove_rport(vha, sess);
> 
> + spin_lock_irqsave(&vha->work_lock, flags);
> + sess->flags &= ~FCF_ASYNC_SENT;
> + sess->deleted = QLA_SESS_DELETED;
> + sess->free_pending = 0;
> + spin_unlock_irqrestore(&vha->work_lock, flags);
> +
> ql_dbg(ql_dbg_disc, vha, 0xf001,
>    "Unregistration of sess %p %8phC finished fcp_cnt %d\n",
> sess, sess->port_name, vha->fcport_count);
> @@ -1185,12 +1185,12 @@ void qlt_unreg_sess(struct fc_port *sess)
> * management from being sent.
> */
> sess->flags |= FCF_ASYNC_SENT;
> + sess->deleted = QLA_SESS_DELETION_IN_PROGRESS;
> spin_unlock_irqrestore(&sess->vha->work_lock, flags);
> 
> if (sess->se_sess)
> vha->hw->tgt.tgt_ops->clear_nacl_from_fcport_map(sess);
> 
> - sess->deleted = QLA_SESS_DELETION_IN_PROGRESS;
> qla2x00_set_fcport_disc_state(sess, DSC_DELETE_PEND);
> sess->last_rscn_gen = sess->rscn_gen;
> sess->last_login_gen = sess->login_gen;
> -- 
> 2.23.1
> 

Looks Good. 

Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>