ifconfig media for ixgbe

[Anton Yuzhaninov]

I'm testing Intel 82599EB network adapter.
Sometimes link is lost.

1. /usr/src/sys/dev/ixgbe/README said

When 82599-based SFP+ devices are connected back to back, they should be set to
the same Speed setting via Ethtool. Results may vary if you mix speed settings.

But manual speed settings for ixgbe don't work under FreeBSD:
# ifconfig -m ix0
ix0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
 
options=407bb<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,JUMBO_MTU,VLAN_HWCSUM,TSO4,TSO6,LRO,VLAN_HWTSO>
 
capabilities=1507bb<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,JUMBO_MTU,VLAN_HWCSUM,TSO4,TSO6,LRO,VLAN_HWFILTER,VLAN_HWTSO,NETMAP>
         ... skipped ...
         media: Ethernet autoselect (10Gbase-SR <full-duplex>)
         status: active
         supported media:
                 media autoselect
                 media 10Gbase-SR
# ifconfig ix0 media 10Gbase-SR
ifconfig: SIOCSIFMEDIA (media): Invalid argument

And as I can see it is limited in driver:
http://bxr.su/FreeBSD/sys/dev/ixgbe/ixgbe.c#1697

README file is outdated?

2. Link sometimes (but no always) lost aster starting 
/usr/src/tools/tools/netmap/pkt-gen
Sometime link restorted after aboring pkt-gen, sometimes only after power off/on
(ifconfig down/up don't help).

Is this netmap related issue?