scsi: lpfc: Ignore ndlp rport mismatch in dev_loss_tmo callbk

[ Upstream commit 23ed62897746f49f195d819ce6edeb1db27d1b72 ]

With repeated port swaps between separate fabrics, there can be multiple
registrations for fabric well known address 0xfffffe.  This can cause ndlp
reference confusion due to the usage of a single ndlp ptr that stores the
rport object in fc_rport struct private storage during transport
registration.  Subsequent registrations update the ndlp->rport field with
the newer rport, so when transport layer triggers dev_loss_tmo for the
earlier registered rport the ndlp->rport private storage is referencing the
newer rport instead of the older rport in dev_loss_tmo callbk.

Because the older ndlp->rport object is already cleaned up elsewhere in
driver code during the time of fabric swap, check that the rport provided
in dev_loss_tmo callbk actually matches the rport stored in the LLDD's
ndlp->rport field.  Otherwise, skip dev_loss_tmo work on a stale rport.

Signed-off-by: Justin Tee <justin.tee@broadcom.com>
Link: https://lore.kernel.org/r/20250131000524.163662-4-justintee8345@gmail.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/scsi/lpfc/lpfc_hbadisc.c b/drivers/scsi/lpfc/lpfc_hbadisc.c
index 45d268d49060e60fd3f0747c8b989423fb958e7e..07cd611f34bd5ff52564578866d19c1219a959db 100644 (file)
--- a/drivers/scsi/lpfc/lpfc_hbadisc.c
+++ b/drivers/scsi/lpfc/lpfc_hbadisc.c
@@ -228,10 +228,16 @@ lpfc_dev_loss_tmo_callbk(struct fc_rport *rport)
        if (ndlp->nlp_state == NLP_STE_MAPPED_NODE)
                return;
 
-       /* check for recovered fabric node */
-       if (ndlp->nlp_state == NLP_STE_UNMAPPED_NODE &&
-           ndlp->nlp_DID == Fabric_DID)
+       /* Ignore callback for a mismatched (stale) rport */
+       if (ndlp->rport != rport) {
+               lpfc_vlog_msg(vport, KERN_WARNING, LOG_NODE,
+                             "6788 fc rport mismatch: d_id x%06x ndlp x%px "
+                             "fc rport x%px node rport x%px state x%x "
+                             "refcnt %u\n",
+                             ndlp->nlp_DID, ndlp, rport, ndlp->rport,
+                             ndlp->nlp_state, kref_read(&ndlp->kref));
                return;
+       }
 
        if (rport->port_name != wwn_to_u64(ndlp->nlp_portname.u.wwn))
                lpfc_printf_vlog(vport, KERN_ERR, LOG_TRACE_EVENT,