From: Nikolay Aleksandrov <niko...@cumulusnetworks.com> Date: Tue, 18 Oct 2016 18:09:48 +0200
> Satish reported a problem with the perm multicast router ports not getting > reenabled after some series of events, in particular if it happens that the > multicast snooping has been disabled and the port goes to disabled state > then it will be deleted from the router port list, but if it moves into > non-disabled state it will not be re-added because the mcast snooping is > still disabled, and enabling snooping later does nothing. > > Here are the steps to reproduce, setup br0 with snooping enabled and eth1 > added as a perm router (multicast_router = 2): > 1. $ echo 0 > /sys/class/net/br0/bridge/multicast_snooping > 2. $ ip l set eth1 down > ^ This step deletes the interface from the router list > 3. $ ip l set eth1 up > ^ This step does not add it again because mcast snooping is disabled > 4. $ echo 1 > /sys/class/net/br0/bridge/multicast_snooping > 5. $ bridge -d -s mdb show > <empty> > > At this point we have mcast enabled and eth1 as a perm router (value = 2) > but it is not in the router list which is incorrect. > > After this change: > 1. $ echo 0 > /sys/class/net/br0/bridge/multicast_snooping > 2. $ ip l set eth1 down > ^ This step deletes the interface from the router list > 3. $ ip l set eth1 up > ^ This step does not add it again because mcast snooping is disabled > 4. $ echo 1 > /sys/class/net/br0/bridge/multicast_snooping > 5. $ bridge -d -s mdb show > router ports on br0: eth1 > > Note: we can directly do br_multicast_enable_port for all because the > querier timer already has checks for the port state and will simply > expire if it's in blocking/disabled. See the comment added by > commit 9aa66382163e7 ("bridge: multicast: add a comment to > br_port_state_selection about blocking state") > > Fixes: 561f1103a2b7 ("bridge: Add multicast_snooping sysfs toggle") > Reported-by: Satish Ashok <sas...@cumulusnetworks.com> > Signed-off-by: Nikolay Aleksandrov <niko...@cumulusnetworks.com> Applied and queued up for -stable, thanks!