Subject: Re: [PATCH net-next,v2] bonding: use WARN_ON_ONCE instead of BUG in alb_upper_dev_walk

From: Jay Vosburgh <[email-masked]>
Date: Tue, 14 Nov 2023 11:40:42 -0800

Zhengchao Shao <[email-masked]> wrote:

>If failed to allocate "tags" or could not find the final upper device from
>start_dev's upper list in bond_verify_device_path(), only the loopback
>detection of the current upper device should be affected, and the system is
>no need to be panic.
>Using WARN_ON_ONCE here is to avoid spamming the log if there's a lot of
>macvlans above the bond.
>
>Signed-off-by: Zhengchao Shao <[email-masked]>
>---
>v2: use WARN_ON_ONCE instead of WARN_ON
>---
> drivers/net/bonding/bond_alb.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
>diff --git a/drivers/net/bonding/bond_alb.c b/drivers/net/bonding/bond_alb.c
>index dc2c7b979656..a7bad0fff8cb 100644
>--- a/drivers/net/bonding/bond_alb.c
>+++ b/drivers/net/bonding/bond_alb.c
>@@ -984,8 +984,10 @@ static int alb_upper_dev_walk(struct net_device *upper,
> 	 */
> 	if (netif_is_macvlan(upper) && !strict_match) {
> 		tags = bond_verify_device_path(bond->dev, upper, 0);
>-		if (IS_ERR_OR_NULL(tags))
>-			BUG();
>+		if (IS_ERR_OR_NULL(tags)) {
>+			WARN_ON_ONCE(1);
>+			return 0;

	Ok, I know this is what I said, but on reflection, I think this
should really return non-zero to terminate the device walk.  

	-J

>+		}
> 		alb_send_lp_vid(slave, upper->dev_addr,
> 				tags[0].vlan_proto, tags[0].vlan_id);
> 		kfree(tags);
>-- 
>2.34.1

---
	-Jay Vosburgh, [email-masked]