On 15 March 2017 at 16:01, Joe Stringer <[email protected]> wrote: > Commit 04f48a68c428 ("ofp-actions: Fix variable length meta-flow OXMs."), on > branch-2.7 as 9554b03d6ab7, attempted to address incorrect encode and decode > of > variable length metaflow fields where the OXM/NXM encoding of the variable > length fields would incorrectly serialize the length. The patch addresses this > by introducing a new per-bridge structure that adds additional metaflow fields > for the variable-length fields on demand when the TLVs are configured by a > controller. > > Unfortunately, in the original patch there was nothing ensuring that flows > referring to variable length fields would retain valid field references when > controllers reconfigure the TLVs. In practice, this could lead to a crash of > ovs-vswitchd by configuring a TLV field, adding a flow which refers to it, > removing the TLV field, then running some traffic that hit the configured > flow. > > This series looks to remedy the situation by reference counting the variable > length fields and preventing a controller from reconfiguring TLV fields when > there are active flows whose match or actions refer to the field. > > This series was applied to master, but given the size of the change and the > minor changes necessary to apply to branch-2.7, I would feel more confident in > backporting it if there was an extra round of review to ensure that nothing > was > missed when this series was first applied to master.
One further concern I have with this series is that while it allows us to fix bugs in OVS 2.7, it would change some files in include/openvswitch/, which I believe indirectly implies that it could break the libopenvswitch ABI, which we try not to do within a release series: http://docs.openvswitch.org/en/latest/internals/contributing/libopenvswitch-abi/ _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
