if_em and large mtu bug?

[Bruce Cran]

Are there any known problems with if_em and jumbo packets? I've found 
that my ssh connection breaks (when running dmesg etc.) if I configure 
the mtu to 9216 via rc.conf - but if I initially use a 1500 byte mtu and 
then manually configure it to 9216 then no problems occur.

I'm running the latest -current: the hardware is:

em0: <Intel(R) PRO/1000 Network Connection 7.3.2> port 0xdc00-0xdc1f mem 
0xfbde0000-0xfbdfffff,0xfbd00000-0xfbd7ffff,0xfbddc000-0xfbddffff irq 16 
at device 0.0 on pci1
em0: Using MSIX interrupts with 3 vectors

-- 
Bruce Cran