2020-01-17 15:33:16

by Amol Grover

Subject: [PATCH 1/2] drivers: scsi: fcoe: fcoe_ctlr: Pass lockdep expression to RCU lists

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 <[email protected]>
---
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

2020-01-17 15:34:41

by Amol Grover

Subject: [PATCH 2/2] drivers: scsi: qedf: qedf_main: Pass lockdep expression to RCU lists

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 <[email protected]>
---
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