[PATCH 2/3] staging: dpaa2-switch: make sure that the VLAN is not already configured

[Ioana Ciornei]

From: Ioana Ciornei <ioana.cior...@nxp.com>

When in the PREPARE state of a switchdev transaction, check if the
requested VLAN is not already configured on the switch port. This keeps
us from getting into a WARNING as below.

[ 1389.683296] dpaa2_ethsw dpsw.0 eth0: VLAN 2 already configured
[ 1389.689125] ------------[ cut here ]------------
[ 1389.694084] eth0: Commit of object (id=1) failed.
[ 1389.698863] WARNING: CPU: 0 PID: 613 at net/switchdev/switchdev.c:277 
switchdev_port_obj_add_now+0xcc/0x110
[ 1389.708589] Modules linked in:
[ 1389.711634] CPU: 0 PID: 613 Comm: bridge Not tainted 
5.9.0-rc2-next-20200828-00112-g7172078477c5 #59
[ 1389.720753] Hardware name: NXP Layerscape LX2160ARDB (DT)
[ 1389.726139] pstate: 40000005 (nZcv daif -PAN -UAO BTYPE=--)
[ 1389.731698] pc : switchdev_port_obj_add_now+0xcc/0x110
[ 1389.736824] lr : switchdev_port_obj_add_now+0xcc/0x110

Signed-off-by: Ioana Ciornei <ioana.cior...@nxp.com>
---
 drivers/staging/fsl-dpaa2/ethsw/ethsw.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/fsl-dpaa2/ethsw/ethsw.c 
b/drivers/staging/fsl-dpaa2/ethsw/ethsw.c
index 20c6326e5dee..d524e92051a3 100644
--- a/drivers/staging/fsl-dpaa2/ethsw/ethsw.c
+++ b/drivers/staging/fsl-dpaa2/ethsw/ethsw.c
@@ -984,10 +984,17 @@ static int dpaa2_switch_port_vlans_add(struct net_device 
*netdev,
        int vid, err = 0, new_vlans = 0;
 
        if (switchdev_trans_ph_prepare(trans)) {
-               for (vid = vlan->vid_begin; vid <= vlan->vid_end; vid++)
+               for (vid = vlan->vid_begin; vid <= vlan->vid_end; vid++) {
                        if (!port_priv->ethsw_data->vlans[vid])
                                new_vlans++;
 
+                       /* Make sure that the VLAN is not already configured
+                        * on the switch port
+                        */
+                       if (port_priv->vlans[vid] & ETHSW_VLAN_MEMBER)
+                               return -EEXIST;
+               }
+
                /* Check if there is space for a new VLAN */
                err = dpsw_get_attributes(ethsw->mc_io, 0, ethsw->dpsw_handle,
                                          &ethsw->sw_attr);
-- 
2.28.0