Comment 0 for bug 1785739

[Impact]
On an APM Merlin (X-Gene2) board, the onboard 1G interface fails to re-establish link when the interface is brought down and back up. Juju + MAAS provider does this after every install (so to configure a bridge), making this config unusable.

This was actually a regression introduced by the fix for LP: #1632739 in 4.4.0-48.69.

[Test Case]
1) From a remote system, start a ping to the IP address of the Merlin board's eth0 interface.
2) On the merlin board: sudo ifconfig eth0 down; sudo ifconfig eth0 up
3) Ping should recover, but doesn't

[Fix]
commit 84a527a41f38a80353f185d05e41b021e1ff672b
Author: Shaohui Xie <email address hidden>
Date: Tue May 10 17:42:26 2016 +0800

    net: phylib: fix interrupts re-enablement in phy_start

[Regression Risk]