tree 01a196cd89ea629ca56643d907765318c0bf9586
parent 8878adba6ab5414c36b693e09fe46c4416072cc7
author Heiner Kallweit <hkallweit1@gmail.com> 1592685342 +0200
committer David S. Miller <davem@davemloft.net> 1592868361 -0700

net: core: try to runtime-resume detached device in __dev_open

A netdevice may be marked as detached because the parent is
runtime-suspended and not accessible whilst interface or link is down.
An example are PCI network devices that go into PCI D3hot, see e.g.
__igc_shutdown() or rtl8169_net_suspend().
If netdevice is down and marked as detached we can only open it if
we runtime-resume it before __dev_open() calls netif_device_present().

Therefore, if netdevice is detached, try to runtime-resume the parent
and only return with an error if it's still detached.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>