[PATCH 03/14] lpfc: Fix premature rpi release for unsolicited TPLS and LS_RJT

[James Smart <jsmart2021@gmail.com>]

A test scenario has a target issuing a TPLS after accepting the
driver's PRLI.  TPLS is not supported by the driver so it rejects
the ELS.  However, the reject was only happening on the primary N_Port.
If the TPLS was to a NPIV vport, not only would it reject the ELS, but
it would act on the TPLS, starting devloss, then unregister from the
SCSI transport and release the node. When devloss expired, it would
access the node again and cause a page faul.

Fix by altering the NPIV code to recognize that a correctly registered
node can reject unsolicited ELS IO and to not unregister with the SCSI
transport and tear the node down.  Add a check of the fc4_xpt_flags so
that only a zero value allows the unreg and teardown.

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 | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/lpfc/lpfc_els.c b/drivers/scsi/lpfc/lpfc_els.c
index df5fc223ddb2..262101e172ad 100644
--- a/drivers/scsi/lpfc/lpfc_els.c
+++ b/drivers/scsi/lpfc/lpfc_els.c
@@ -5295,6 +5295,7 @@ lpfc_cmpl_els_rsp(struct lpfc_hba *phba, struct lpfc_iocbq *cmdiocb,
 	 */
 	if (phba->sli_rev == LPFC_SLI_REV4 &&
 	    (vport && vport->port_type == LPFC_NPIV_PORT) &&
+	    !(ndlp->fc4_xpt_flags & SCSI_XPT_REGD) &&
 	    ndlp->nlp_flag & NLP_RELEASE_RPI) {
 		lpfc_sli4_free_rpi(phba, ndlp->nlp_rpi);
 		spin_lock_irq(&ndlp->lock);
@@ -5598,11 +5599,12 @@ lpfc_els_rsp_reject(struct lpfc_vport *vport, uint32_t rejectError,
 	}
 
 	/* The NPIV instance is rejecting this unsolicited ELS. Make sure the
-	 * node's assigned RPI needs to be released as this node will get
-	 * freed.
+	 * node's assigned RPI gets released provided this node is not already
+	 * registered with the transport.
 	 */
 	if (phba->sli_rev == LPFC_SLI_REV4 &&
-	    vport->port_type == LPFC_NPIV_PORT) {
+	    vport->port_type == LPFC_NPIV_PORT &&
+	    !(ndlp->fc4_xpt_flags & SCSI_XPT_REGD)) {
 		spin_lock_irq(&ndlp->lock);
 		ndlp->nlp_flag |= NLP_RELEASE_RPI;
 		spin_unlock_irq(&ndlp->lock);
-- 
2.26.2