4.16-stable review patch. If anyone has any objections, please let me know. ------------------ From: Xin Long <lucien.xin@xxxxxxxxx> [ Upstream commit ddea788c63094f7c483783265563dd5b50052e28 ] After Commit 8a8efa22f51b ("bonding: sync netpoll code with bridge"), it would set slave_dev npinfo in slave_enable_netpoll when enslaving a dev if bond->dev->npinfo was set. However now slave_dev npinfo is set with bond->dev->npinfo before calling slave_enable_netpoll. With slave_dev npinfo set, __netpoll_setup called in slave_enable_netpoll will not call slave dev's .ndo_netpoll_setup(). It causes that the lower dev of this slave dev can't set its npinfo. One way to reproduce it: # modprobe bonding # brctl addbr br0 # brctl addif br0 eth1 # ifconfig bond0 192.168.122.1/24 up # ifenslave bond0 eth2 # systemctl restart netconsole # ifenslave bond0 br0 # ifconfig eth2 down # systemctl restart netconsole The netpoll won't really work. This patch is to remove that slave_dev npinfo setting in bond_enslave(). Fixes: 8a8efa22f51b ("bonding: sync netpoll code with bridge") Signed-off-by: Xin Long <lucien.xin@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/bonding/bond_main.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -1660,8 +1660,7 @@ int bond_enslave(struct net_device *bond } /* switch(bond_mode) */ #ifdef CONFIG_NET_POLL_CONTROLLER - slave_dev->npinfo = bond->dev->npinfo; - if (slave_dev->npinfo) { + if (bond->dev->npinfo) { if (slave_enable_netpoll(new_slave)) { netdev_info(bond_dev, "master_dev is using netpoll, but new slave device does not support netpoll\n"); res = -EBUSY;