target/linux/generic/backport-5.4/707-v5.7-0007-net-dsa-b53-Deny-enslaving-port-7-for-7278-into-a-br.patch

   1 From 31bfc2d42cae6e8b1440fc5db3f0aba6c5d7e602 Mon Sep 17 00:00:00 2001
   2 From: Florian Fainelli <f.fainelli@gmail.com>
   3 Date: Mon, 30 Mar 2020 14:38:49 -0700
   4 Subject: [PATCH] net: dsa: b53: Deny enslaving port 7 for 7278 into a bridge
   5
   6 On 7278, port 7 connects to the ASP which should only receive frames
   7 through the use of CFP rules, it is not desirable to have it be part of
   8 a bridge at all since that would make it pick up unwanted traffic that
   9 it may not even be able to filter or sustain.
  10
  11 Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
  12 Signed-off-by: David S. Miller <davem@davemloft.net>
  13 ---
  14  drivers/net/dsa/b53/b53_common.c | 6 ++++++
  15  1 file changed, 6 insertions(+)
  16
  17 --- a/drivers/net/dsa/b53/b53_common.c
  18 +++ b/drivers/net/dsa/b53/b53_common.c
  19 @@ -1770,6 +1770,12 @@ int b53_br_join(struct dsa_switch *ds, i
  20         u16 pvlan, reg;
  21         unsigned int i;
  22
  23 +       /* On 7278, port 7 which connects to the ASP should only receive
  24 +        * traffic from matching CFP rules.
  25 +        */
  26 +       if (dev->chip_id == BCM7278_DEVICE_ID && port == 7)
  27 +               return -EINVAL;
  28 +
  29         /* Make this port leave the all VLANs join since we will have proper
  30          * VLAN entries from now on
  31          */