[PATCH net-next 2/2] bonding: fix link recovery in mode 2 when updelay is nonzero

[Jonathan Toppins]

Before this change when a bond in mode 2 lost link, all of its slaves
lost link, the bonding device would never recover even after the
expiration of updelay. This change removes the updelay when the bond
currently has no usable links. Conforming to bonding.txt section 13.1
paragraph 4.

Signed-off-by: Jonathan Toppins <jtoppins@xxxxxxxxxx>
---
 drivers/net/bonding/bond_main.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 1cd4e71916f8..6c4348245d1f 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -2529,7 +2529,16 @@ static int bond_miimon_inspect(struct bonding *bond)
 	struct slave *slave;
 	bool ignore_updelay;
 
-	ignore_updelay = !rcu_dereference(bond->curr_active_slave);
+	if (BOND_MODE(bond) == BOND_MODE_ACTIVEBACKUP) {
+		ignore_updelay = !rcu_dereference(bond->curr_active_slave);
+	} else {
+		struct bond_up_slave *usable_slaves;
+
+		usable_slaves = rcu_dereference(bond->usable_slaves);
+
+		if (usable_slaves && usable_slaves->count == 0)
+			ignore_updelay = true;
+	}
 
 	bond_for_each_slave_rcu(bond, slave, iter) {
 		bond_propose_link_state(slave, BOND_LINK_NOCHANGE);
-- 
2.31.1