On 2018-07-19 18:20, Michal Soltys wrote: > On 07/19/2018 01:41 AM, Mahesh Bandewar wrote: >> From: Mahesh Bandewar <mahe...@google.com> >> >> Commit b89f04c61efe ("bonding: deliver link-local packets with >> skb->dev set to link that packets arrived on") changed the behavior >> of how link-local-multicast packets are processed. The change in >> the behavior broke some legacy use cases where these packets are >> expected to arrive on bonding master device also. >> >> This patch passes the packet to the stack with the link it arrived >> on as well as passes to the bonding-master device to preserve the >> legacy use case. >> >> Fixes: b89f04c61efe ("bonding: deliver link-local packets with >> skb->dev set to link that packets arrived on") >> Reported-by: Michal Soltys <sol...@ziu.info> >> Signed-off-by: Mahesh Bandewar <mahe...@google.com> >> --- >> v2: Added Fixes tag. >> v1: Initial patch. >> drivers/net/bonding/bond_main.c | 17 +++++++++++++++-- >> 1 file changed, 15 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/net/bonding/bond_main.c >> b/drivers/net/bonding/bond_main.c >> index 9a2ea3c1f949..1d3b7d8448f2 100644 >> --- a/drivers/net/bonding/bond_main.c >> +++ b/drivers/net/bonding/bond_main.c >> @@ -1177,9 +1177,22 @@ static rx_handler_result_t >> bond_handle_frame(struct sk_buff **pskb) >> } >> } >> - /* don't change skb->dev for link-local packets */ >> - if (is_link_local_ether_addr(eth_hdr(skb)->h_dest)) >> + /* Link-local multicast packets should be passed to the >> + * stack on the link they arrive as well as pass them to the >> + * bond-master device. These packets are mostly usable when >> + * stack receives it with the link on which they arrive >> + * (e.g. LLDP) but there may be some legacy behavior that >> + * expects these packets to appear on bonding master too. > > I'd really change the comment from: > > "These packets are mostly usable when stack receives it with the link on > which they arrive (e.g. LLDP) but there may be some legacy behavior that > expects these packets to appear on bonding master too." > > to something like: > > "These packets are mostly usable when stack receives it with the link on > which they arrive, but they also must be available on aggregations. Some > of the use cases include (but are not limited to): LLDP agents that must > be able to operate both on enslaved interfaces as well as on bonds > themselves; linux bridges that must be able to process/pass BPDUs from > attached bonds when any kind of stp version is enabled on the network." > > It's a bit longer, but clarifies the reasons more precisely (without > going too deep into features like group_fwd_mask). >
Anyway, any chance for that patch to get merged ? It would be great to get the correct functionality back asap. As for the comment, I'll submit a trivial patch expanding/clarifying it later (or I can resubmit adjusted v3 if it's ok with Mahesh).