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From: Sasha Levin <sashal@kernel.org>
To: linux-kernel@vger.kernel.org,
	stable@vger.kernel.org
Cc: Justin Tee <justin.tee@broadcom.com>,
	"Martin K . Petersen" <martin.petersen@oracle.com>,
	Sasha Levin <sashal@kernel.org>,
	james.smart@broadcom.com,
	dick.kennedy@broadcom.com,
	jejb@linux.ibm.com,
	linux-scsi@vger.kernel.org
Subject: [PATCH AUTOSEL 6.6 06/22] scsi: lpfc: Release hbalock before calling lpfc_worker_wake_up()
Date: Sun,  7 Apr 2024 09:12:05 -0400
Message-ID: <20240407131231.1051652-6-sashal@kernel.org>
In-Reply-To: <20240407131231.1051652-1-sashal@kernel.org>
References: <20240407131231.1051652-1-sashal@kernel.org>
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From: Justin Tee <justin.tee@broadcom.com>

[ Upstream commit ded20192dff31c91cef2a04f7e20e60e9bb887d3 ]

lpfc_worker_wake_up() calls the lpfc_work_done() routine, which takes the
hbalock.  Thus, lpfc_worker_wake_up() should not be called while holding the
hbalock to avoid potential deadlock.

Signed-off-by: Justin Tee <justin.tee@broadcom.com>
Link: https://lore.kernel.org/r/20240305200503.57317-7-justintee8345@gmail.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/scsi/lpfc/lpfc_els.c     | 20 ++++++++++----------
 drivers/scsi/lpfc/lpfc_hbadisc.c |  5 ++---
 drivers/scsi/lpfc/lpfc_sli.c     | 14 +++++++-------
 3 files changed, 19 insertions(+), 20 deletions(-)

diff --git a/drivers/scsi/lpfc/lpfc_els.c b/drivers/scsi/lpfc/lpfc_els.c
index 18b8325fd419e..44d3ada9fbbcb 100644
--- a/drivers/scsi/lpfc/lpfc_els.c
+++ b/drivers/scsi/lpfc/lpfc_els.c
@@ -4432,23 +4432,23 @@ lpfc_els_retry_delay(struct timer_list *t)
 	unsigned long flags;
 	struct lpfc_work_evt  *evtp = &ndlp->els_retry_evt;
 
+	/* Hold a node reference for outstanding queued work */
+	if (!lpfc_nlp_get(ndlp))
+		return;
+
 	spin_lock_irqsave(&phba->hbalock, flags);
 	if (!list_empty(&evtp->evt_listp)) {
 		spin_unlock_irqrestore(&phba->hbalock, flags);
+		lpfc_nlp_put(ndlp);
 		return;
 	}
 
-	/* We need to hold the node by incrementing the reference
-	 * count until the queued work is done
-	 */
-	evtp->evt_arg1  = lpfc_nlp_get(ndlp);
-	if (evtp->evt_arg1) {
-		evtp->evt = LPFC_EVT_ELS_RETRY;
-		list_add_tail(&evtp->evt_listp, &phba->work_list);
-		lpfc_worker_wake_up(phba);
-	}
+	evtp->evt_arg1 = ndlp;
+	evtp->evt = LPFC_EVT_ELS_RETRY;
+	list_add_tail(&evtp->evt_listp, &phba->work_list);
 	spin_unlock_irqrestore(&phba->hbalock, flags);
-	return;
+
+	lpfc_worker_wake_up(phba);
 }
 
 /**
diff --git a/drivers/scsi/lpfc/lpfc_hbadisc.c b/drivers/scsi/lpfc/lpfc_hbadisc.c
index 5154eeaee0ec3..93703ab6ce037 100644
--- a/drivers/scsi/lpfc/lpfc_hbadisc.c
+++ b/drivers/scsi/lpfc/lpfc_hbadisc.c
@@ -257,7 +257,9 @@ lpfc_dev_loss_tmo_callbk(struct fc_rport *rport)
 		if (evtp->evt_arg1) {
 			evtp->evt = LPFC_EVT_DEV_LOSS;
 			list_add_tail(&evtp->evt_listp, &phba->work_list);
+			spin_unlock_irqrestore(&phba->hbalock, iflags);
 			lpfc_worker_wake_up(phba);
+			return;
 		}
 		spin_unlock_irqrestore(&phba->hbalock, iflags);
 	} else {
@@ -275,10 +277,7 @@ lpfc_dev_loss_tmo_callbk(struct fc_rport *rport)
 			lpfc_disc_state_machine(vport, ndlp, NULL,
 						NLP_EVT_DEVICE_RM);
 		}
-
 	}
-
-	return;
 }
 
 /**
diff --git a/drivers/scsi/lpfc/lpfc_sli.c b/drivers/scsi/lpfc/lpfc_sli.c
index 4dfadf254a727..9dab33686a931 100644
--- a/drivers/scsi/lpfc/lpfc_sli.c
+++ b/drivers/scsi/lpfc/lpfc_sli.c
@@ -1217,9 +1217,9 @@ lpfc_set_rrq_active(struct lpfc_hba *phba, struct lpfc_nodelist *ndlp,
 	empty = list_empty(&phba->active_rrq_list);
 	list_add_tail(&rrq->list, &phba->active_rrq_list);
 	phba->hba_flag |= HBA_RRQ_ACTIVE;
+	spin_unlock_irqrestore(&phba->hbalock, iflags);
 	if (empty)
 		lpfc_worker_wake_up(phba);
-	spin_unlock_irqrestore(&phba->hbalock, iflags);
 	return 0;
 out:
 	spin_unlock_irqrestore(&phba->hbalock, iflags);
@@ -11369,18 +11369,18 @@ lpfc_sli_post_recovery_event(struct lpfc_hba *phba,
 	unsigned long iflags;
 	struct lpfc_work_evt  *evtp = &ndlp->recovery_evt;
 
+	/* Hold a node reference for outstanding queued work */
+	if (!lpfc_nlp_get(ndlp))
+		return;
+
 	spin_lock_irqsave(&phba->hbalock, iflags);
 	if (!list_empty(&evtp->evt_listp)) {
 		spin_unlock_irqrestore(&phba->hbalock, iflags);
+		lpfc_nlp_put(ndlp);
 		return;
 	}
 
-	/* Incrementing the reference count until the queued work is done. */
-	evtp->evt_arg1  = lpfc_nlp_get(ndlp);
-	if (!evtp->evt_arg1) {
-		spin_unlock_irqrestore(&phba->hbalock, iflags);
-		return;
-	}
+	evtp->evt_arg1 = ndlp;
 	evtp->evt = LPFC_EVT_RECOVER_PORT;
 	list_add_tail(&evtp->evt_listp, &phba->work_list);
 	spin_unlock_irqrestore(&phba->hbalock, iflags);
-- 
2.43.0