| Message ID | 20250204145549.1216254-7-idosch@nvidia.com (mailing list archive) |
|---|---|
| State | New |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | vxlan: Age FDB entries based on Rx traffic | expand |
On 2/4/25 16:55, Ido Schimmel wrote: > Currently, the VXLAN driver ages out FDB entries based on their 'used' > time which is refreshed by both the Tx and Rx paths. This means that an > FDB entry will not age out if traffic is only forwarded to the target > host: > > # ip link add name vx1 up type vxlan id 10010 local 192.0.2.1 dstport 4789 learning ageing 10 > # bridge fdb add 00:11:22:33:44:55 dev vx1 self dynamic dst 198.51.100.1 > # bridge fdb get 00:11:22:33:44:55 br vx1 self > 00:11:22:33:44:55 dev vx1 dst 198.51.100.1 self > # mausezahn vx1 -a own -b 00:11:22:33:44:55 -c 0 -p 100 -q & > # sleep 20 > # bridge fdb get 00:11:22:33:44:55 br vx1 self > 00:11:22:33:44:55 dev vx1 dst 198.51.100.1 self > > This is wrong as an FDB entry will remain present when we no longer have > an indication that the host is still behind the current remote. It is > also inconsistent with the bridge driver: > > # ip link add name br1 up type bridge ageing_time $((10 * 100)) > # ip link add name swp1 up master br1 type dummy > # bridge fdb add 00:11:22:33:44:55 dev swp1 master dynamic > # bridge fdb get 00:11:22:33:44:55 br br1 > 00:11:22:33:44:55 dev swp1 master br1 > # mausezahn br1 -a own -b 00:11:22:33:44:55 -c 0 -p 100 -q & > # sleep 20 > # bridge fdb get 00:11:22:33:44:55 br br1 > Error: Fdb entry not found. > > Solve this by aging out entries based on their 'updated' time, which is > not refreshed by the Tx path: > > # ip link add name vx1 up type vxlan id 10010 local 192.0.2.1 dstport 4789 learning ageing 10 > # bridge fdb add 00:11:22:33:44:55 dev vx1 self dynamic dst 198.51.100.1 > # bridge fdb get 00:11:22:33:44:55 br vx1 self > 00:11:22:33:44:55 dev vx1 dst 198.51.100.1 self > # mausezahn vx1 -a own -b 00:11:22:33:44:55 -c 0 -p 100 -q & > # sleep 20 > # bridge fdb get 00:11:22:33:44:55 br vx1 self > Error: Fdb entry not found. > > But is refreshed by the Rx path: > > # ip address add 192.0.2.1/32 dev lo > # ip link add name vx1 up type vxlan id 10010 local 192.0.2.1 dstport 4789 localbypass > # ip link add name vx2 up type vxlan id 20010 local 192.0.2.1 dstport 4789 learning ageing 10 > # bridge fdb add 00:11:22:33:44:55 dev vx1 self static dst 127.0.0.1 vni 20010 > # mausezahn vx1 -a 00:aa:bb:cc:dd:ee -b 00:11:22:33:44:55 -c 0 -p 100 -q & > # sleep 20 > # bridge fdb get 00:aa:bb:cc:dd:ee br vx2 self > 00:aa:bb:cc:dd:ee dev vx2 dst 127.0.0.1 self > # pkill mausezahn > # sleep 20 > # bridge fdb get 00:aa:bb:cc:dd:ee br vx2 self > Error: Fdb entry not found. > > Reviewed-by: Petr Machata <petrm@nvidia.com> > Signed-off-by: Ido Schimmel <idosch@nvidia.com> > --- > drivers/net/vxlan/vxlan_core.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
diff --git a/drivers/net/vxlan/vxlan_core.c b/drivers/net/vxlan/vxlan_core.c index c75fcb0679ac..01797becae09 100644 --- a/drivers/net/vxlan/vxlan_core.c +++ b/drivers/net/vxlan/vxlan_core.c @@ -2860,7 +2860,7 @@ static void vxlan_cleanup(struct timer_list *t) if (f->flags & NTF_EXT_LEARNED) continue; - timeout = READ_ONCE(f->used) + vxlan->cfg.age_interval * HZ; + timeout = READ_ONCE(f->updated) + vxlan->cfg.age_interval * HZ; if (time_before_eq(timeout, jiffies)) { netdev_dbg(vxlan->dev, "garbage collect %pM\n",