On 8/21/25 1:09 PM, Xavier Simonart via dev wrote: > vif1(hv1) - ls - localnet - ls - vif2(hv2) > > In this configuration, with one logical switch with two vif (vif1 on > hv1 and vif2 on hv2), and a localnet port (localnet), traffic from vif1 to > vif2 goes through localnet. A vif entry update in fdb was lost if the sb > transaction was failing. > > A transaction could fail in the following scenario: > - When packet from vif1 is received by br-int on hv1, vif1_mac is inserted in > FDB with port=vif1 [1]. > - When the packet is received on hv2 by localnet, if it is received before the > FDB update [1], then vif1_mac is inserted in FDB with port=localnet [2]. > This transaction, when sent, will fail [A]. The transaction might be sent > later (in some time) as sent by ovn-controller (while packet was forwarded > by OVS w/o OVN intervention). > - When vif2 replies (e.g. ARP reply, echo reply), vif2_mac is inserted in > FDB [3] with port=vif2. If the reply packet is handled in hv2 before FDB > update [2] is sent, both updates [2] and [3] are sent at the same time. > Hence, if the transaction fails [A], vif2_mac is not inserted in FDB. > - Finally, when reply hits hv1, if vif2_mac is not in FDB, an entry for > vif2_mac will be inserted in FDB with port=localnet. > > Hence, at the end of the game, the FDB entry for vif2_mac is localnet, and > vif2 stops receiving packets until it sends one (and updates FDB with > port=vif2). > > This patch fixes this by resubmitting FDB updates for VIF entries if the > transaction failed. > > Reported-at: https://issues.redhat.com/browse/FDP-1341 > Signed-off-by: Xavier Simonart <[email protected]> > Signed-off-by: Ales Musil <[email protected]> > (cherry picked from commit 7ff2c6be57493ef438d893109b24f65571ca641e) > ---
Hi Xavier, Thanks for the backport. The original commit is only on main, was this backport patch intended for both 25.03 and 24.03 branches? It doesn't apply cleanly on 25.03 and the conflict is non-trivial. We need at least a backport patch for 25.03 before we can apply this one. Would you be able to prepare one for 25.03 as well? Thanks, Dumitru _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
