Re: [PATCH net-next] net: dsa: realtek: rtl8366rb: Fix up port isolation

On Sat, Jul 11, 2026 at 8:03 PM Luiz Angelo Daros de Luca
[off-list ref] wrote:

quoted

-               /* Start with all ports completely isolated */
-               ret = rtl8366rb_port_set_isolation(priv, dp->index, 0);
-               if (ret)
-                       return ret;

If you don't isolate the ports, what is the default port status?

Hm as I wrote in the commit message:

"the next loop in the setup code, over the
user ports, isolate all the ports from each other, so only the CPU
port can see them."

It looks like this:

        /* Configure user ports */
        dsa_switch_for_each_port(dp, ds) {
                if (!dsa_port_is_user(dp))
                        continue;

                /* Forward only to the CPU, isolate from all other ports */
                ret = rtl8366rb_port_set_isolation(priv, dp->index,
upports_mask);
                if (ret)
                        return ret;

                /* If we support cascade switches, it should also include the
                 * downstream DSA ports.
                 */
                downports_mask |= BIT(dp->index);
        }

upports_mask is the bitmask for all CPU ports, so that should do what is
expected?

Yours,
Linus Walleij