[PATCH 05/11] lpfc: Fix Node recovery when driver is handling simultaneous PLOGIs

[James Smart <jsmart2021@gmail.com>]

When lpfc is handling a solicited and unsolicited PLOGI with another
initiator, the remote initiator is never recovered. The node for the
initiator is erroneouosly removed and all resources released.

In lpfc_cmpl_els_plogi, when lpfc_els_retry returns a failure
code, the driver is calling the state machine with a device remove
event because the remote port is not currently registered with
the SCSI or nvme transports. The issue is that on a PLOGI "collision"
the driver correctly aborts the solicited PLOGI and allows the
unsolicited PLOGI to complete the process, but this process is
interrupted with a device_rm event.

Introduce logic in the PLOGI completion to capture the PLOGI collision
event and jump out of the routine.  This will avoid removal of the
node.  If there is no collision, the normal node removal will occur.

Fixes: 	52edb2caf675 ("scsi: lpfc: Remove ndlp when a PLOGI/ADISC/PRLI/REG_RPI ultimately fails")
Cc: <stable@vger.kernel.org> # v5.11+

Co-developed-by: Justin Tee <justin.tee@broadcom.com>
Signed-off-by: Justin Tee <justin.tee@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
---
 drivers/scsi/lpfc/lpfc_els.c | 21 ++++++++++++++++++---
 1 file changed, 18 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/lpfc/lpfc_els.c b/drivers/scsi/lpfc/lpfc_els.c
index 118f0d50968a..933927f738c7 100644
--- a/drivers/scsi/lpfc/lpfc_els.c
+++ b/drivers/scsi/lpfc/lpfc_els.c
@@ -2007,9 +2007,20 @@ lpfc_cmpl_els_plogi(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
 			lpfc_disc_state_machine(vport, ndlp, cmdiocb,
 						NLP_EVT_CMPL_PLOGI);
 
-		/* As long as this node is not registered with the scsi or nvme
-		 * transport, it is no longer an active node.  Otherwise
-		 * devloss handles the final cleanup.
+		/* If a PLOGI collision occurred, the node needs to continue
+		 * with the reglogin process.
+		 */
+		spin_lock_irq(&ndlp->lock);
+		if ((ndlp->nlp_flag & (NLP_ACC_REGLOGIN | NLP_RCV_PLOGI)) &&
+		    ndlp->nlp_state == NLP_STE_REG_LOGIN_ISSUE) {
+			spin_unlock_irq(&ndlp->lock);
+			goto out;
+		}
+		spin_unlock_irq(&ndlp->lock);
+
+		/* No PLOGI collision and the node is not registered with the
+		 * scsi or nvme transport. It is no longer an active node. Just
+		 * start the device remove process.
 		 */
 		if (!(ndlp->fc4_xpt_flags & (SCSI_XPT_REGD | NVME_XPT_REGD))) {
 			spin_lock_irq(&ndlp->lock);
@@ -4629,6 +4640,10 @@ lpfc_cmpl_els_rsp(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
 	    (vport && vport->port_type == LPFC_NPIV_PORT) &&
 	    ndlp->nlp_flag & NLP_RELEASE_RPI) {
 		lpfc_sli4_free_rpi(phba, ndlp->nlp_rpi);
+		spin_lock_irq(&ndlp->lock);
+		ndlp->nlp_rpi = LPFC_RPI_ALLOC_ERROR;
+		ndlp->nlp_flag &= ~NLP_RELEASE_RPI;
+		spin_unlock_irq(&ndlp->lock);
 		lpfc_drop_node(vport, ndlp);
 	}
 
-- 
2.26.2