Re: [PATCH net-next v2 3/6] net: bridge: add 802.1Qat stream reservation admission control

Luke Howard <[email protected]> Sat, 6 Jun 2026 08:36:52 +1000
Newsgroups dev.linux.lists.bridge,org.kernel.vger.linux-kernel,org.kernel.vger.linux-kselftest,org.kernel.vger.netdev
Message-ID <[email protected]>
> But the concept comes from the 802.1Q spec. The spec describes different types
> of FDB entries. One of these is Dynamic Reservation Entries, which are created
> from the Stream Reservation Protocol.
> The issue here is the Marvell switch has an implementation where we need to
> know if an entry is a Dynamic Reservation Entry. But the linux bridge has a
> simplified version of the FDB described in 802.1Q.
> By adding a way to distinguish between the type of FDB entries, it's possible
> to program a Marvell which has this distinction between Dynamic Reservation
> Entries (or AVB entries) and other entries.

If we only care about the multicast case, and we can depend on snooping being enabled and flooding disabled, then I think Dynamic Reservation Entries collapse to permanent MDB entries. Unicast is trickier.

The issue of reclassifying (or dropping) frames that share a SRP class PCP is separate. I think it could be done with a tc-flower entry that reclassifies all ingress traffic with SRP PCPs (e.g. see 802.1Q Table 6-5) and then a per-stream egress entry that sets the queue and priority.