tree d32c15cc4bc8fea3659db08a9d735fb516037591
parent a936b1ef37ce1e996533878f4b23944f9444dcdf
author Julian Wiedmann <jwi@linux.vnet.ibm.com> 1524135129 +0200
committer David S. Miller <davem@davemloft.net> 1524422551 -0400

s390/qeth: fix MAC address update sequence

When changing the MAC address on a L2 qeth device, current code first
unregisters the old address, then registers the new one.
If HW rejects the new address (or the IO fails), the device ends up with
no operable address at all.

Re-order the code flow so that the old address only gets dropped if the
new address was registered successfully. While at it, add logic to catch
some corner-cases.

Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>