bge0: discard frame w/o packet header

[John Polstra]

I have a Dell SC1435 server running an i386 -current system from
around the end of December, with a few selected updates applied.  It
had been running reliably until early this morning, when the
following sequence of events happened.  First, this message was
logged:

  Feb 15 07:14:29 rock kernel: bge0: discard frame w/o packet header

About 2 minutes later, at 07:16:30, the last /var/log/maillog entry
was logged.  (This machine is under constant assault from spambots
trying dictionary attacks.  It is rare for more than 15 seconds to
pass without something being logged in the maillog file.)

30 seconds after that came another bge message:

  Feb 15 07:17:00 rock kernel: bge0: discard frame w/o packet header

At that point, all network connectivity was gone.  The machine didn't
respond to pings.  Worse, its remote management controller, which uses
ASF and shares the same network interface, was also unresponsive to
pings.  To get the machine back, I had to ask somebody working at the
colocation facility to power-cycle it.

The "discard frame w/o packet header" message comes from ether_input()
if it gets an mbuf that doesn't have the M_PKTHDR flag set.  That
can't happen unless something is very wrong with the system.  I'd like
to make it a panic.  At least then the machine would reboot instead of
just becoming unreachable.  Any objections?

Some other nearby warnings should also be panics, in my opinion:

  discard frame w/o leading ethernet header ...

  discard frame w/o interface pointer ...

and, maybe:

  discard oversize frame ...

Opinions?

John

PS - dmesg output for bge0:

bge0: <Broadcom NetXtreme Gigabit Ethernet Controller, ASIC rev. 0x4201> mem 0xefef0000-0xefefffff
irq 33 at device 0.0 on pci1
miibus0: <MII bus> on bge0
brgphy0: <BCM5750 10/100/1000baseTX PHY> on miibus0
brgphy0:  10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, 1000baseTX, 1000baseTX-FDX, auto
bge0: Ethernet address: 00:18:8b:78:b7:b1

I'm running the following revisions of the driver sources:

  if_bge.c      1.172
  if_bgereg.h   1.65
  brgphy.c      1.52

These aren't completely up-to-date, but I don't see any recent
changes that would have anything to do with the messages that were
logged.