sk0 link bouncing

[YongHyeon PYUN]

On Wed, Jul 04, 2012 at 12:08:16PM +0200, Willem Jan Withagen wrote:
> Hi,
> 
> I've got tons of these since I stopped loading the port with traffic....
> It seems to have a pretty steady 27 min interval.
> 
> Jul  4 07:00:05 freetest kernel: sk0: link state changed to DOWN
> Jul  4 07:00:05 freetest kernel: sk0: link state changed to UP
> Jul  4 07:27:21 freetest kernel: sk0: link state changed to DOWN
> Jul  4 07:27:21 freetest kernel: sk0: link state changed to UP
> Jul  4 07:53:48 freetest kernel: sk0: link state changed to DOWN
> Jul  4 07:53:48 freetest kernel: sk0: link state changed to UP
> Jul  4 08:21:16 freetest kernel: sk0: link state changed to DOWN
> Jul  4 08:21:16 freetest kernel: sk0: link state changed to UP
> Jul  4 08:48:10 freetest kernel: sk0: link state changed to DOWN
> Jul  4 08:48:11 freetest kernel: sk0: link state changed to UP
> Jul  4 09:13:38 freetest kernel: sk0: link state changed to DOWN
> Jul  4 09:13:38 freetest kernel: sk0: link state changed to UP
> Jul  4 09:39:06 freetest kernel: sk0: link state changed to DOWN
> Jul  4 09:39:06 freetest kernel: sk0: link state changed to UP
> 
> Very recent 10-current install with std GENERIC kernel.
> FreeBSD freetest.digiware.nl 10.0-CURRENT FreeBSD 10.0-CURRENT #1: Sat
> Jun 30 09:35:43 UTC 2012
> root at freetest.digiware.nl:/usr/obj/usr/src/sys/GENERIC  amd64
> 
> The port is connected to a basic netgear 10/100/1000 switch with nothing
> modified in the config of that port.
> Other connections do not seem to suffer from disconnecting.
> 
> Used the server to 'zfs send' a 360G backup to, and then it did not do
> anything like this, the port just stayed up.
> 
> Suggestions where of what to look for this?

Probably you have to implement link state change handler for
Marvell controller(i.e.  sk_marv_miibus_statchg()).  Locking for
MII access should be revisited too.
Sorry, don't have spare time to do that.

> 
> Thanx,
> --WjW