This is a note to let you know that I've just added the patch titled bonding: fix lockdep splat in bond_miimon_commit() to the 6.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: bonding-fix-lockdep-splat-in-bond_miimon_commit.patch and it can be found in the queue-6.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit d56cd43655fe0a8dad3de52f8509eb2ca7f1648f Author: Eric Dumazet <edumazet@xxxxxxxxxx> Date: Tue Dec 20 13:08:31 2022 +0000 bonding: fix lockdep splat in bond_miimon_commit() [ Upstream commit 42c7ded0eeacd2ba5db599205c71c279dc715de7 ] bond_miimon_commit() is run while RTNL is held, not RCU. WARNING: suspicious RCU usage 6.1.0-syzkaller-09671-g89529367293c #0 Not tainted ----------------------------- drivers/net/bonding/bond_main.c:2704 suspicious rcu_dereference_check() usage! Fixes: e95cc44763a4 ("bonding: do failover when high prio link up") Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx> Reported-by: syzbot <syzkaller@xxxxxxxxxxxxxxxx> Cc: Hangbin Liu <liuhangbin@xxxxxxxxx> Cc: Jay Vosburgh <j.vosburgh@xxxxxxxxx> Cc: Veaceslav Falico <vfalico@xxxxxxxxx> Cc: Andy Gospodarek <andy@xxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20221220130831.1480888-1-edumazet@xxxxxxxxxx Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index b108f2f4adc2..fce9301c8ebb 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -2653,10 +2653,12 @@ static void bond_miimon_link_change(struct bonding *bond, static void bond_miimon_commit(struct bonding *bond) { - struct slave *slave, *primary; + struct slave *slave, *primary, *active; bool do_failover = false; struct list_head *iter; + ASSERT_RTNL(); + bond_for_each_slave(bond, slave, iter) { switch (slave->link_new_state) { case BOND_LINK_NOCHANGE: @@ -2699,8 +2701,8 @@ static void bond_miimon_commit(struct bonding *bond) bond_miimon_link_change(bond, slave, BOND_LINK_UP); - if (!rcu_access_pointer(bond->curr_active_slave) || slave == primary || - slave->prio > rcu_dereference(bond->curr_active_slave)->prio) + active = rtnl_dereference(bond->curr_active_slave); + if (!active || slave == primary || slave->prio > active->prio) do_failover = true; continue;