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* [Linux-kernel-mentees] [PATCH 1/2 RESEND] scsi: fcoe: fcoe_ctlr: Pass lockdep expression to RCU lists
@ 2020-02-12  7:23 Amol Grover
  2020-02-12  7:25 ` [Linux-kernel-mentees] [PATCH 2/2 RESEND] scsi: qedf: qedf_main: " Amol Grover
  0 siblings, 1 reply; 2+ messages in thread
From: Amol Grover @ 2020-02-12  7:23 UTC (permalink / raw)
  To: Hannes Reinecke, James E.J. Bottomley, Martin K. Petersen
  Cc: linux-scsi, Paul E . McKenney, linux-kernel, Joel Fernandes,
	linux-kernel-mentees

lport->disc.rports and disc->rports are traversed using
list_for_each_entry_rcu outside an RCU read-side critical section but
under the protection of lport->disc.disc_mutex and disc->disc_mutex
respectively.

Hence, add corresponding lockdep expression to silence false-positive
lockdep warnings, and harden RCU lists.

Signed-off-by: Amol Grover <frextrite@gmail.com>
---
 drivers/scsi/fcoe/fcoe_ctlr.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/fcoe/fcoe_ctlr.c b/drivers/scsi/fcoe/fcoe_ctlr.c
index 1791a393795d..0f59992c9cd9 100644
--- a/drivers/scsi/fcoe/fcoe_ctlr.c
+++ b/drivers/scsi/fcoe/fcoe_ctlr.c
@@ -2167,7 +2167,8 @@ static void fcoe_ctlr_disc_stop_locked(struct fc_lport *lport)
 	struct fc_rport_priv *rdata;
 
 	mutex_lock(&lport->disc.disc_mutex);
-	list_for_each_entry_rcu(rdata, &lport->disc.rports, peers) {
+	list_for_each_entry_rcu(rdata, &lport->disc.rports, peers,
+				lockdep_is_held(&lport->disc.disc_mutex)) {
 		if (kref_get_unless_zero(&rdata->kref)) {
 			fc_rport_logoff(rdata);
 			kref_put(&rdata->kref, fc_rport_destroy);
@@ -2703,7 +2704,8 @@ static unsigned long fcoe_ctlr_vn_age(struct fcoe_ctlr *fip)
 
 	next_time = jiffies + msecs_to_jiffies(FIP_VN_BEACON_INT * 10);
 	mutex_lock(&lport->disc.disc_mutex);
-	list_for_each_entry_rcu(rdata, &lport->disc.rports, peers) {
+	list_for_each_entry_rcu(rdata, &lport->disc.rports, peers,
+				lockdep_is_held(&lport->disc.disc_mutex)) {
 		if (!kref_get_unless_zero(&rdata->kref))
 			continue;
 		frport = fcoe_ctlr_rport(rdata);
@@ -3061,7 +3063,8 @@ static void fcoe_ctlr_vn_disc(struct fcoe_ctlr *fip)
 	mutex_lock(&disc->disc_mutex);
 	callback = disc->pending ? disc->disc_callback : NULL;
 	disc->pending = 0;
-	list_for_each_entry_rcu(rdata, &disc->rports, peers) {
+	list_for_each_entry_rcu(rdata, &disc->rports, peers,
+				lockdep_is_held(&disc->disc_mutex)) {
 		if (!kref_get_unless_zero(&rdata->kref))
 			continue;
 		frport = fcoe_ctlr_rport(rdata);
-- 
2.24.1

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^ permalink raw reply	[flat|nested] 2+ messages in thread

* [Linux-kernel-mentees] [PATCH 2/2 RESEND] scsi: qedf: qedf_main: Pass lockdep expression to RCU lists
  2020-02-12  7:23 [Linux-kernel-mentees] [PATCH 1/2 RESEND] scsi: fcoe: fcoe_ctlr: Pass lockdep expression to RCU lists Amol Grover
@ 2020-02-12  7:25 ` " Amol Grover
  0 siblings, 0 replies; 2+ messages in thread
From: Amol Grover @ 2020-02-12  7:25 UTC (permalink / raw)
  To: Hannes Reinecke, James E.J. Bottomley, Martin K. Petersen
  Cc: linux-scsi, Paul E . McKenney, linux-kernel, Joel Fernandes,
	linux-kernel-mentees

lport->disc.rports is traversed using list_for_each_entry_rcu
outside an RCU read-side critical section but under the protection
of lport->disc.disc_mutex.

Hence, add corresponding lockdep expression to silence false-positive
lockdep warnings, and harden RCU lists.

Signed-off-by: Amol Grover <frextrite@gmail.com>
---
 drivers/scsi/qedf/qedf_main.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/qedf/qedf_main.c b/drivers/scsi/qedf/qedf_main.c
index 604856e72cfb..17eab7f8cf05 100644
--- a/drivers/scsi/qedf/qedf_main.c
+++ b/drivers/scsi/qedf/qedf_main.c
@@ -420,7 +420,8 @@ static void qedf_link_recovery(struct work_struct *work)
 	 * ADISC since the rport is in state ready.
 	 */
 	mutex_lock(&lport->disc.disc_mutex);
-	list_for_each_entry_rcu(rdata, &lport->disc.rports, peers) {
+	list_for_each_entry_rcu(rdata, &lport->disc.rports, peers,
+				lockdep_is_held(&lport->disc.disc_mutex)) {
 		if (kref_get_unless_zero(&rdata->kref)) {
 			fc_rport_login(rdata);
 			kref_put(&rdata->kref, fc_rport_destroy);
-- 
2.24.1

_______________________________________________
Linux-kernel-mentees mailing list
Linux-kernel-mentees@lists.linuxfoundation.org
https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees

^ permalink raw reply	[flat|nested] 2+ messages in thread

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2020-02-12  7:23 [Linux-kernel-mentees] [PATCH 1/2 RESEND] scsi: fcoe: fcoe_ctlr: Pass lockdep expression to RCU lists Amol Grover
2020-02-12  7:25 ` [Linux-kernel-mentees] [PATCH 2/2 RESEND] scsi: qedf: qedf_main: " Amol Grover

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