On 15 Dec 2025, at 12:58, Toke Høiland-Jørgensen wrote:
> Eelco Chaudron <[email protected]> writes: > >> On 11 Dec 2025, at 12:50, Toke Høiland-Jørgensen wrote: >> >>> The openvswitch teardown code will immediately call >>> ovs_netdev_detach_dev() in response to a NETDEV_UNREGISTER notification. >>> It will then start the dp_notify_work workqueue, which will later end up >>> calling the vport destroy() callback. This callback takes the RTNL to do >>> another ovs_netdev_detach_port(), which in this case is unnecessary. >>> This causes extra pressure on the RTNL, in some cases leading to >>> "unregister_netdevice: waiting for XX to become free" warnings on >>> teardown. >>> >>> We can straight-forwardly avoid the extra RTNL lock acquisition by >>> checking the device flags before taking the lock, and skip the locking >>> altogether if the IFF_OVS_DATAPATH flag has already been unset. >>> >>> Fixes: b07c26511e94 ("openvswitch: fix vport-netdev unregister") >>> Tested-by: Adrian Moreno <[email protected]> >>> Signed-off-by: Toke Høiland-Jørgensen <[email protected]> >> >> Guess the change looks good, but I’m waiting for some feedback from >> Adrian to see if this change makes sense. > > OK. > >> Any luck reproducing the issue it’s supposed to fix? > > We got a report from the customer that originally reported it (who had > their own reproducer) that this patch fixes their issue to the point > where they can now delete ~2000 pods/node without triggering the > unregister_netdevice warning at all (where before it triggered at around > ~500 pod deletions). So that's encouraging :) That’s good news; just wanted to make sure we are not chasing a red herring :) Acked-by: Eelco Chaudron [email protected] _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
