scsi: fcoe: don't recurse on the netdev's ops lock

fcoe_link_speed_update() calls __ethtool_get_link_ksettings() on the
lport's netdev, which will soon take the dev's ops lock. Some notifier
callers already arrive with this lock held. Switch to
netif_get_link_ksettings() and adjust the explicit call sites to take
the netdev lock explicitly.

Within fcoe_device_notification() try to only query the link speed
from notifiers which announce link state change (UP / CHANGE),
DOWN / GOING_DOWN notifiers are slightly sketchy when it comes
to ops locking right now, and the code already special-cases
those by maintaining the local link_possible variable.

Also take the lock in bnx2fc_net_config(), even though I think
that bnx2fc call sites are largely irrelevant since it's not
an ops-locked driver.

Link: https://patch.msgid.link/20260603012840.2254293-11-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/scsi/bnx2fc/bnx2fc_fcoe.c b/drivers/scsi/bnx2fc/bnx2fc_fcoe.c
index 26e0ff380860dbce0e11d3baa752fc2f01901336..c95b084cad69fab10f1aecd2045c27a2b496be1d 100644 (file)
--- a/drivers/scsi/bnx2fc/bnx2fc_fcoe.c
+++ b/drivers/scsi/bnx2fc/bnx2fc_fcoe.c
@@ -17,6 +17,7 @@
 #include "bnx2fc.h"
 
 #include <linux/ethtool.h>
+#include <net/netdev_lock.h>
 
 static struct list_head adapter_list;
 static struct list_head if_list;
@@ -815,7 +816,9 @@ static int bnx2fc_net_config(struct fc_lport *lport, struct net_device *netdev)
        port->fcoe_pending_queue_active = 0;
        timer_setup(&port->timer, fcoe_queue_timer, 0);
 
+       netdev_lock_ops(netdev);
        fcoe_link_speed_update(lport);
+       netdev_unlock_ops(netdev);
 
        if (!lport->vport) {
                if (fcoe_get_wwn(netdev, &wwnn, NETDEV_FCOE_WWNN))

diff --git a/drivers/scsi/fcoe/fcoe.c b/drivers/scsi/fcoe/fcoe.c
index 534596c6d76c5441f4d23669896471ddf33f1f48..438ac7c3a9e3fd548a42779c4d753320ec79a854 100644 (file)
--- a/drivers/scsi/fcoe/fcoe.c
+++ b/drivers/scsi/fcoe/fcoe.c
@@ -25,6 +25,7 @@
 #include <scsi/scsicam.h>
 #include <scsi/scsi_transport.h>
 #include <scsi/scsi_transport_fc.h>
+#include <net/netdev_lock.h>
 #include <net/rtnetlink.h>
 
 #include <scsi/fc/fc_encaps.h>
@@ -737,7 +738,9 @@ static int fcoe_netdev_config(struct fc_lport *lport, struct net_device *netdev)
        port->fcoe_pending_queue_active = 0;
        timer_setup(&port->timer, fcoe_queue_timer, 0);
 
+       netdev_lock_ops(netdev);
        fcoe_link_speed_update(lport);
+       netdev_unlock_ops(netdev);
 
        if (!lport->vport) {
                if (fcoe_get_wwn(netdev, &wwnn, NETDEV_FCOE_WWNN))
@@ -1841,6 +1844,7 @@ static int fcoe_device_notification(struct notifier_block *notifier,
                break;
        case NETDEV_UP:
        case NETDEV_CHANGE:
+               fcoe_link_speed_update(lport);
                break;
        case NETDEV_CHANGEMTU:
                if (netdev->fcoe_mtu)
@@ -1871,8 +1875,6 @@ static int fcoe_device_notification(struct notifier_block *notifier,
                                "from netdev netlink\n", event);
        }
 
-       fcoe_link_speed_update(lport);
-
        cdev = fcoe_ctlr_to_ctlr_dev(ctlr);
 
        if (link_possible && !fcoe_link_ok(lport)) {

diff --git a/drivers/scsi/fcoe/fcoe_transport.c b/drivers/scsi/fcoe/fcoe_transport.c
index 88d85fc9a52a3fd25a56f879ffee77c3dae5b4b5..2bbb9a38e61d7f483b3c4c8fa52d75a7fd28d9a4 100644 (file)
--- a/drivers/scsi/fcoe/fcoe_transport.c
+++ b/drivers/scsi/fcoe/fcoe_transport.c
@@ -111,6 +111,8 @@ static inline u32 eth2fc_speed(u32 eth_port_speed)
  * fcoe_link_speed_update() - Update the supported and actual link speeds
  * @lport: The local port to update speeds for
  *
+ * Caller must hold the netdev's ops lock.
+ *
  * Returns: 0 if the ethtool query was successful
  *          -1 if the ethtool query failed
  */
@@ -119,7 +121,7 @@ int fcoe_link_speed_update(struct fc_lport *lport)
        struct net_device *netdev = fcoe_get_netdev(lport);
        struct ethtool_link_ksettings ecmd;
 
-       if (!__ethtool_get_link_ksettings(netdev, &ecmd)) {
+       if (!netif_get_link_ksettings(netdev, &ecmd)) {
                lport->link_supported_speeds &= ~(FC_PORTSPEED_1GBIT  |
                                                  FC_PORTSPEED_10GBIT |
                                                  FC_PORTSPEED_20GBIT |