Re: [PATCH net-next v2 2/2] bonding: fix link recovery in mode 2 when updelay is nonzero

From: Jay Vosburgh
Date: Wed Nov 23 2022 - 01:25:37 EST


Jonathan Toppins <jtoppins@xxxxxxxxxx> wrote:

>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.
>
>Fixes: 41f891004063 ("bonding: ignore updelay param when there is no active slave")
>Signed-off-by: Jonathan Toppins <jtoppins@xxxxxxxxxx>

This looks correct, although I suspect it would affect more than
just balance-xor ("mode 2"); if memory serves, balance-rr mode operates
similarly.

Acked-by: Jay Vosburgh <jay.vosburgh@xxxxxxxxxxxxx>

-J

>---
>
>Notes:
> v2:
> * added fixes tag and reposted to net tree
>
> 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 f298b9b3eb77..f747bd60d399 100644
>--- a/drivers/net/bonding/bond_main.c
>+++ b/drivers/net/bonding/bond_main.c
>@@ -2536,7 +2536,16 @@ 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
>