linux/net
Vladimir Oltean a324d3d48f net: dsa: make assisted_learning_on_cpu_port bypass offloaded LAG interfaces
Given the following topology, and focusing only on Box A:

         Box A
         +----------------------------------+
         | Board 1         br0              |
         |             +---------+          |
         |            /           \         |
         |            |           |         |
         |            |         bond0       |
         |            |        +-----+      |
         |192.168.1.1 |       /       \     |
         |  eno0     swp0    swp1    swp2   |
         +---|--------|-------|-------|-----+
             |        |       |       |
             +--------+       |       |
               Cable          |       |
                         Cable|       |Cable
               Cable          |       |
             +--------+       |       |
             |        |       |       |
         +---|--------|-------|-------|-----+
         |  eno0     swp0    swp1    swp2   |
         |192.168.1.2 |       \       /     |
         |            |        +-----+      |
         |            |         bond0       |
         |            |           |         |
         |            \           /         |
         |             +---------+          |
         | Board 2         br0              |
         +----------------------------------+
         Box B

The assisted_learning_on_cpu_port logic will see that swp0 is bridged
with a "foreign interface" (bond0) and will therefore install all
addresses learnt by the software bridge towards bond0 (including the
address of eno0 on Box B) as static addresses towards the CPU port.

But that's not what we want - bond0 is not really a "foreign interface"
but one we can offload including L2 forwarding from/towards it. So we
need to refine our logic for assisted learning such that, whenever we
see an address learnt on a non-DSA interface, we search through the tree
for any port that offloads that non-DSA interface.

Some confusion might arise as to why we search through the whole tree
instead of just the local switch returned by dsa_slave_dev_lower_find.
Or a different angle of the same confusion: why does
dsa_slave_dev_lower_find(br_dev) return a single dp that's under br_dev
instead of the whole list of bridged DSA ports?

To answer the second question, it should be enough to install the static
FDB entry on the CPU port of a single switch in the tree, because
dsa_port_fdb_add uses DSA_NOTIFIER_FDB_ADD which ensures that all other
switches in the tree get notified of that address, and add the entry
themselves using dsa_towards_port().

This should help understand the answer to the first question: the port
returned by dsa_slave_dev_lower_find may not be on the same switch as
the ports that offload the LAG. Nonetheless, if the driver implements
.crosschip_lag_join and .crosschip_bridge_join as mv88e6xxx does, there
still isn't any reason for trapping addresses learnt on the remote LAG
towards the CPU, and we should prevent that.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-02-06 14:51:51 -08:00
..
6lowpan
9p net: remove redundant 'depends on NET' 2021-01-27 17:04:12 -08:00
802
8021q Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-01-14 18:34:50 -08:00
appletalk net: appletalk: fix kerneldoc warnings 2020-10-30 11:48:17 -07:00
atm net: atm: pppoatm: use new API for wakeup tasklet 2021-01-29 18:24:05 -08:00
ax25
batman-adv net: remove redundant 'depends on NET' 2021-01-27 17:04:12 -08:00
bluetooth net: remove redundant 'depends on NET' 2021-01-27 17:04:12 -08:00
bpf Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-01-20 12:16:11 -08:00
bpfilter net: remove redundant 'depends on NET' 2021-01-27 17:04:12 -08:00
bridge net: bridge: mcast: Use ERR_CAST instead of ERR_PTR(PTR_ERR()) 2021-02-06 10:51:01 -08:00
caif
can linux-can-next-for-5.12-20210127 2021-01-27 18:53:10 -08:00
ceph libceph: fix "Boolean result is used in bitwise operation" warning 2021-01-21 16:49:59 +01:00
core Revert "net: Have netpoll bring-up DSA management interface" 2021-02-06 14:42:57 -08:00
dcb net: dcb: use obj-$(CONFIG_DCB) form in net/Makefile 2021-01-27 17:03:52 -08:00
dccp dccp: Return the correct errno code 2021-02-06 11:15:28 -08:00
decnet net: decnet: fix netdev refcount leaking on error path 2021-01-27 17:33:46 -08:00
dns_resolver net: remove redundant 'depends on NET' 2021-01-27 17:04:12 -08:00
dsa net: dsa: make assisted_learning_on_cpu_port bypass offloaded LAG interfaces 2021-02-06 14:51:51 -08:00
ethernet net: datagram: fix some kernel-doc markups 2020-11-17 14:15:03 -08:00
ethtool ethtool: Expose the number of lanes in use 2021-02-03 18:37:29 -08:00
hsr net: hsr: align sup_multicast_addr in struct hsr_priv to u16 boundary 2021-02-02 08:57:18 -08:00
ieee802154 treewide: rename nla_strlcpy to nla_strscpy. 2020-11-16 08:08:54 -08:00
ife net: remove redundant 'depends on NET' 2021-01-27 17:04:12 -08:00
ipv4 Revert "net: ipv4: handle DSA enabled master network devices" 2021-02-06 14:42:57 -08:00
ipv6 net/core: move gro function declarations to separate header 2021-02-04 18:37:57 -08:00
iucv net/af_iucv: build SG skbs for TRANS_HIPER sockets 2021-01-28 20:36:22 -08:00
kcm net: group skb_shinfo zerocopy related bits together. 2021-01-07 16:08:37 -08:00
key af_key: relax availability checks for skb size calculation 2021-01-04 10:05:50 +01:00
l2tp lsm,selinux: pass flowi_common instead of flowi to the LSM hooks 2020-11-23 18:36:21 -05:00
l3mdev net: l3mdev: use obj-$(CONFIG_NET_L3_MASTER_DEV) form in net/Makefile 2021-01-27 17:03:52 -08:00
lapb net: lapb: Copy the skb before sending a packet 2021-02-02 08:40:48 -08:00
llc net: remove redundant 'depends on NET' 2021-01-27 17:04:12 -08:00
mac80211 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-02-02 14:21:31 -08:00
mac802154 net: mac802154: convert tasklets to use new tasklet_setup() API 2020-11-07 10:40:56 -08:00
mpls mpls: drop skb's dst in mpls_forward() 2020-11-03 12:55:53 -08:00
mptcp mptcp: pm: add lockdep assertions 2021-02-06 14:35:47 -08:00
ncsi net/ncsi: Use real net-device for response handler 2020-12-23 12:22:23 -08:00
netfilter netfilter: move handlers to net/ip_vs.h 2021-02-04 18:37:57 -08:00
netlabel Merge https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-11-19 19:08:46 -08:00
netlink netlink: add tracepoint at NL_SET_ERR_MSG 2021-02-04 18:05:59 -08:00
netrom
nfc Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-01-28 17:09:31 -08:00
nsh
openvswitch net: openvswitch: add log message for error case 2021-01-14 16:32:14 -08:00
packet net: packet: make pkt_sk() inline 2021-01-29 17:38:55 -08:00
phonet
psample net: remove redundant 'depends on NET' 2021-01-27 17:04:12 -08:00
qrtr net: qrtr: fix null-ptr-deref in qrtr_ns_remove 2021-01-05 16:50:09 -08:00
rds net/rds: restrict iovecs length for RDS_CMSG_RDMA_ARGS 2021-02-02 08:44:08 -08:00
rfkill rfkill: add a reason to the HW rfkill state 2020-12-11 12:47:17 +01:00
rose rose: Fix Null pointer dereference in rose_send_frame() 2020-11-20 10:04:58 -08:00
rxrpc rxrpc: call udp_tunnel_encap_enable in rxrpc_open_socket 2021-02-04 18:37:15 -08:00
sched net: sched: Return the correct errno code 2021-02-06 11:15:28 -08:00
sctp sctp: remove the NETIF_F_SG flag before calling skb_segment 2021-01-16 19:05:59 -08:00
smc net/smc: use memcpy instead of snprintf to avoid out of bounds read 2021-01-12 20:22:01 -08:00
strparser
sunrpc SUNRPC: Handle 0 length opaque XDR object data properly 2021-01-25 15:59:12 -05:00
switchdev Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-01-28 17:09:31 -08:00
tipc tipc: remove duplicated code in tipc_msg_create 2021-01-27 18:50:07 -08:00
tls net/tls: Except bond interface from some TLS checks 2021-01-18 20:48:40 -08:00
unix networking changes for the 5.10 merge window 2020-10-15 18:42:13 -07:00
vmw_vsock vsock: fix the race conditions in multi-transport support 2021-02-01 19:54:30 -08:00
wireless This time, only RTNL locking reduction fallout. 2021-02-02 18:40:42 -08:00
x25 net: x25: Remove unimplemented X.25-over-LLC code stubs 2020-12-12 17:15:33 -08:00
xdp xsk: Clear pool even for inactive queues 2021-01-19 22:47:04 +01:00
xfrm Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec 2021-01-21 11:05:10 -08:00
compat.c iov_iter: transparently handle compat iovecs in import_iovec 2020-10-03 00:02:13 -04:00
devres.c
Kconfig wimax: move out to staging 2020-10-29 19:27:45 +01:00
Makefile net: l3mdev: use obj-$(CONFIG_NET_L3_MASTER_DEV) form in net/Makefile 2021-01-27 17:03:52 -08:00
socket.c for-5.11/io_uring-2020-12-14 2020-12-16 12:44:05 -08:00
sysctl_net.c