4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Florian Fainelli <f.fainelli@xxxxxxxxx> [ Upstream commit 4078b76cac68e50ccf1f76a74e7d3d5788aec3fe ] We need to check the return value of phy_connect_direct() in dsa_slave_phy_connect() otherwise we may be continuing the initialization of a slave network device with a PHY that already attached somewhere else and which will soon be in error because the PHY device is in error. The conditions for such an error to occur are that we have a port of our switch that is not disabled, and has the same port number as a PHY address (say both 5) that can be probed using the DSA slave MII bus. We end-up having this slave network device find a PHY at the same address as our port number, and we try to attach to it. A slave network (e.g: port 0) has already attached to our PHY device, and we try to re-attach it with a different network device, but since we ignore the error we would end-up initializating incorrect device references by the time the slave network interface is opened. The code has been (re)organized several times, making it hard to provide an exact Fixes tag, this is a bugfix nonetheless. Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/dsa/slave.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) --- a/net/dsa/slave.c +++ b/net/dsa/slave.c @@ -1103,10 +1103,8 @@ static int dsa_slave_phy_connect(struct /* Use already configured phy mode */ if (p->phy_interface == PHY_INTERFACE_MODE_NA) p->phy_interface = p->phy->interface; - phy_connect_direct(slave_dev, p->phy, dsa_slave_adjust_link, - p->phy_interface); - - return 0; + return phy_connect_direct(slave_dev, p->phy, dsa_slave_adjust_link, + p->phy_interface); } static int dsa_slave_phy_setup(struct dsa_slave_priv *p,