Re: [PATCH] net: dsa: mv88e6xxx: avoid error message on remove from VLAN 0
From: Vivien Didelot
Date: Fri May 31 2019 - 10:34:50 EST
Hi Nikita,
On Fri, 31 May 2019 10:35:14 +0300, Nikita Yushchenko <nikita.yoush@xxxxxxxxxxxxxxxxxx> wrote:
> When non-bridged, non-vlan'ed mv88e6xxx port is moving down, error
> message is logged:
>
> failed to kill vid 0081/0 for device eth_cu_1000_4
>
> This is caused by call from __vlan_vid_del() with vin set to zero, over
> call chain this results into _mv88e6xxx_port_vlan_del() called with
> vid=0, and mv88e6xxx_vtu_get() called from there returns -EINVAL.
>
> On symmetric path moving port up, call goes through
> mv88e6xxx_port_vlan_prepare() that calls mv88e6xxx_port_check_hw_vlan()
> that returns -EOPNOTSUPP for zero vid.
>
> This patch changes mv88e6xxx_vtu_get() to also return -EOPNOTSUPP for
> zero vid, then this error code is explicitly cleared in
> dsa_slave_vlan_rx_kill_vid() and error message is no longer logged.
>
> Signed-off-by: Nikita Yushchenko <nikita.yoush@xxxxxxxxxxxxxxxxxx>
> ---
> drivers/net/dsa/mv88e6xxx/chip.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c
> index 28414db979b0..6b77fde5f0e4 100644
> --- a/drivers/net/dsa/mv88e6xxx/chip.c
> +++ b/drivers/net/dsa/mv88e6xxx/chip.c
> @@ -1392,7 +1392,7 @@ static int mv88e6xxx_vtu_get(struct mv88e6xxx_chip *chip, u16 vid,
> int err;
>
> if (!vid)
> - return -EINVAL;
> + return -EOPNOTSUPP;
>
> entry->vid = vid - 1;
> entry->valid = false;
I'm not sure that I like the semantic of it, because the driver can actually
support VID 0 per-se, only the kernel does not use VLAN 0. Thus I would avoid
calling the port_vlan_del() ops for VID 0, directly into the upper DSA layer.
Florian, Andrew, wouldn't the following patch be more adequate?
diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index 1e2ae9d59b88..80f228258a92 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -1063,6 +1063,10 @@ static int dsa_slave_vlan_rx_kill_vid(struct net_device *dev, __be16 proto,
struct bridge_vlan_info info;
int ret;
+ /* VID 0 has a special meaning and is never programmed in hardware */
+ if (!vid)
+ return 0;
+
/* Check for a possible bridge VLAN entry now since there is no
* need to emulate the switchdev prepare + commit phase.
*/
Thanks,
Vivien