[RFC PATCH net-next 1/7] net: dsa: only bring down user ports assigned to a given DSA master

This is an adaptation of commit c0a8a9c27493 ("net: dsa: automatically
bring user ports down when master goes down") for multiple DSA masters.
When a DSA master goes down, only the user ports under its control
should go down too, the others can still send/receive traffic.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
---
 net/dsa/slave.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index 2b153b366118..f76c96e27868 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c

@@ -2364,6 +2364,9 @@ static int dsa_slave_netdevice_event(struct notifier_block *nb,
 			if (!dsa_port_is_user(dp))
 				continue;
 
+			if (dp->cpu_dp != cpu_dp)
+				continue;
+
 			list_add(&dp->slave->close_list, &close_list);
 		}
 

-- 
2.25.1