With SK_DEBUG defined, I get only one extra line: skc0 at pci2 dev 0 function 0: ioapic0 pin 18 (irq7) skc0: bad VPD resource id: expected 82 got 0 skc0: (null) rev. (0x2) sk0 at skc0 port A: Ethernet address 00:1b:11:c0:7e:8f >>> sk_jumbo_buf = 0x0xffff800046390000 panic: sk0: unknown device type 182