[PATCH net-next v2 08/11] net: sched: don't recurse on the netdev ops lock in qdiscs
From: Jakub Kicinski <kuba@kernel.org>
Date: 2026-06-03 01:28:58
Also in:
linux-leds
Subsystem:
cbs/etf/taprio qdiscs, networking [general], tc subsystem, the rest · Maintainers:
Vinicius Costa Gomes, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Jamal Hadi Salim, Jiri Pirko, Linus Torvalds
cbs_set_port_rate() and taprio_set_picos_per_byte() are reached from
two paths and both already hold the device's ops lock:
*_change(), via tc_modify_qdisc() which calls netdev_lock_ops(dev)
before dispatching to the qdisc ops.
*_dev_notifier() on NETDEV_UP / NETDEV_CHANGE, where caller
holds the ops lock across the notifier chain.
Switch to netif_get_link_ksettings() to avoid deadlock once
__ethtool_get_link_ksettings() starts taking the netdev lock.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
net/sched/sch_cbs.c | 2 +-
net/sched/sch_taprio.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/net/sched/sch_cbs.c b/net/sched/sch_cbs.c
index b952353ec2a5..85b41ffc63ff 100644
--- a/net/sched/sch_cbs.c
+++ b/net/sched/sch_cbs.c@@ -327,7 +327,7 @@ static void cbs_set_port_rate(struct net_device *dev, struct cbs_sched_data *q) s64 port_rate; int err; - err = __ethtool_get_link_ksettings(dev, &ecmd); + err = netif_get_link_ksettings(dev, &ecmd); if (err < 0) goto skip;
diff --git a/net/sched/sch_taprio.c b/net/sched/sch_taprio.c
index d6b981e5df11..e83cbce62a54 100644
--- a/net/sched/sch_taprio.c
+++ b/net/sched/sch_taprio.c@@ -1299,7 +1299,7 @@ static void taprio_set_picos_per_byte(struct net_device *dev, int picos_per_byte; int err; - err = __ethtool_get_link_ksettings(dev, &ecmd); + err = netif_get_link_ksettings(dev, &ecmd); if (err < 0) goto skip;
--
2.54.0