9323ac3670
Both the felix DSA driver and ocelot switchdev driver declare
dev->features & NETIF_F_HW_VLAN_CTAG_FILTER under certain circumstances*,
so the 8021q module will add VID 0 to our RX filter when the port goes
up, to ensure 802.1p traffic is not dropped.
We treat VID 0 as a special value (OCELOT_STANDALONE_PVID) which
deliberately does not have a struct ocelot_bridge_vlan associated with
it. Instead, this gets programmed to the VLAN table in ocelot_vlan_init().
If we allow external calls to modify VID 0, we reach the following
situation:
# ip link add br0 type bridge vlan_filtering 1 && ip link set br0 up
# ip link set swp0 master br0
# ip link set swp0 up # this adds VID 0 to ocelot->vlans with untagged=false
bridge vlan
port vlan-id
swp0 1 PVID Egress Untagged # the bridge also adds VID 1
br0 1 PVID Egress Untagged
# bridge vlan add dev swp0 vid 100 untagged
Error: mscc_ocelot_switch_lib: Port with egress-tagged VLANs cannot have more than one egress-untagged (native) VLAN.
This configuration should have been accepted, because
ocelot_port_manage_port_tag() should select OCELOT_PORT_TAG_NATIVE.
Yet it isn't, because we have an entry in ocelot->vlans which says
VID 0 should be egress-tagged, something the hardware can't do.
Fix this by suppressing additions/deletions on VID 0 and managing this
VLAN exclusively using OCELOT_STANDALONE_PVID.
*DSA toggles it when the port becomes VLAN-aware by joining a VLAN-aware
bridge. Ocelot declares it unconditionally for some reason.
Fixes: 54c319846086 ("net: mscc: ocelot: enforce FDB isolation when VLAN-unaware")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.