uma_zalloc_arg: zone "256" with non-sleepable exclusive rw ifnet_rw @ /usr/src/sys/net/if.c:414

Hi,

I see this "malloc with non-sleepable" on current during boot.
It's strange that I don't see it if I boot via pxe/nfs.

if_alloc() calls ifindex_alloc_locked() under IFNET_WLOCK() which
might call if_grow().
Looks like a regression from r196553.

igb6: <Intel(R) PRO/1000 Network Connection version - 2.0.7> port
0x8020-0x803f mem
0xd0820000-0xd083ffff,0xd0400000-0xd07fffff,0xd08c4000-0xd08c7fff irq
54 at device 0.0 on pci144
uma_zalloc_arg: zone "256" with the following non-sleepable locks held:
exclusive rw ifnet_rw (ifnet_rw) r = 0 (0xffffffff80e9aac0) locked _at_
/usr/src/sys/net/if.c:414
KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0x2a
kdb_backtrace() at kdb_backtrace+0x37
_witness_debugger() at _witness_debugger+0x2e
witness_warn() at witness_warn+0x2c4
uma_zalloc_arg() at uma_zalloc_arg+0x335
malloc() at malloc+0xbe
if_grow() at if_grow+0x2f
if_alloc() at if_alloc+0x2f3
igb_attach() at igb_attach+0x1a3a
device_attach() at device_attach+0x69
bus_generic_attach() at bus_generic_attach+0x1a
acpi_pci_attach() at acpi_pci_attach+0x14f
device_attach() at device_attach+0x69
bus_generic_attach() at bus_generic_attach+0x1a
acpi_pcib_attach() at acpi_pcib_attach+0x1a7
acpi_pcib_pci_attach() at acpi_pcib_pci_attach+0x95
device_attach() at device_attach+0x69
bus_generic_attach() at bus_generic_attach+0x1a
acpi_pci_attach() at acpi_pci_attach+0x14f
device_attach() at device_attach+0x69
bus_generic_attach() at bus_generic_attach+0x1a
acpi_pcib_attach() at acpi_pcib_attach+0x1a7
acpi_pcib_acpi_attach() at acpi_pcib_acpi_attach+0x1fd
device_attach() at device_attach+0x69
bus_generic_attach() at bus_generic_attach+0x1a
acpi_attach() at acpi_attach+0xac4
device_attach() at device_attach+0x69
bus_generic_attach() at bus_generic_attach+0x1a
nexus_acpi_attach() at nexus_acpi_attach+0x69
device_attach() at device_attach+0x69
bus_generic_new_pass() at bus_generic_new_pass+0xd6
bus_set_pass() at bus_set_pass+0x7a
configure() at configure+0xa
mi_startup() at mi_startup+0x77
btext() at btext+0x2c
igb6: Ethernet address: 00:1b:21:73:59:14

-- 
wbr,
pluknet