boot time crash in if_detach_internal()

[Chris Torek]

>Can you provide a backtrace that leads to this?

Sure.  In case it's not obvious, the __rw_rlock at the top of the
trace is working on a lock that has never been initialized (the
first of the two ipv4 PCBs).

Chris

Booting...
GDB: no debug ports present
KDB: debugger backends: ddb
KDB: current backend: ddb
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FreeBSD 10.0-CURRENT #2: Sun Mar 31 01:32:38 MDT 2013
    torek at dev.torek.net:/usr/obj/usr/src/sys/GENERIC amd64
FreeBSD clang version 3.2 (tags/RELEASE_32/final 170710) 20121221
WARNING: WITNESS option enabled, expect reduced performance.
CPU: Intel(R) Core(TM) i3-3220 CPU @ 3.30GHz (3292.28-MHz K8-class CPU)
  Origin = "GenuineIntel"  Id = 0x306a9  Family = 0x6  Model = 0x3a  Stepping = 9
  Features=0x8fa3ab7f<FPU,VME,DE,PSE,TSC,MSR,PAE,CX8,APIC,SEP,PGE,CMOV,PAT,PSE36,DTS,MMX,FXSR,SSE,SSE2,SS,PBE>
  Features2=0xa1bae217<SSE3,PCLMULQDQ,DTES64,DS_CPL,SSSE3,CX16,xTPR,PDCM,PCID,SSE4.1,SSE4.2,x2APIC,POPCNT,TSCDLT,F16C,HV>
  AMD Features=0x28100800<SYSCALL,NX,RDTSCP,LM>
  AMD Features2=0x1<LAHF>
  TSC: P-state invariant
real memory  = 536870912 (512 MB)
avail memory = 472559616 (450 MB)
Event timer "LAPIC" quality 400
ACPI APIC Table: <BHYVE  BVMADT  >
FreeBSD/SMP: Multiprocessor System Detected: 2 CPUs
FreeBSD/SMP: 2 package(s) x 1 core(s)
 cpu0 (BSP): APIC ID:  0
 cpu1 (AP): APIC ID:  1
random device not loaded; using insecure entropy
ioapic0: Changing APIC ID to 2
ioapic0 <Version 1.1> irqs 0-16 on motherboard
module_register_init: MOD_LOAD (vesa, 0xffffffff80c38e80, 0) error 19
kbd0 at kbdmux0
acpi0: <BHYVE BVXSDT> on motherboard
atrtc0: <AT realtime clock> port 0x70-0x71,0x72-0x77 irq 8 on acpi0
Event timer "RTC" frequency 32768 Hz quality 0
Timecounter "ACPI-fast" frequency 3579545 Hz quality 900
acpi_timer0: <32-bit timer at 3.579545MHz> port 0x408-0x40b on acpi0
pcib0: <ACPI Host-PCI bridge> port 0xcf8-0xcff on acpi0
pci0: <ACPI PCI bus> on pcib0
pcib0: no PRT entry for 0.31.INTA
virtio_pci0: <VirtIO PCI Network adapter> port 0x2000-0x201f at device 1.0 on pci0
vtnet0: <VirtIO Networking Adapter> on virtio_pci0
virtio_pci0: host features: 0x18020 <Status,MrgRxBuf,MacAddress>
virtio_pci0: negotiated features: 0x18020 <Status,MrgRxBuf,MacAddress>
vtnet0: Ethernet address: 00:a0:98:36:6d:e8
virtio_pci0: exhausted all interrupt allocation attempts
vtnet0: cannot setup virtqueue interrupts


Fatal trap 12: page fault while in kernel mode
cpuid = 0; apic id = 00
fault virtual address	= 0x378
fault code		= supervisor read data, page not present
instruction pointer	= 0x20:0xffffffff808894bb
stack pointer	        = 0x28:0xffffffff818434b0
frame pointer	        = 0x28:0xffffffff81843550
code segment		= base 0x0, limit 0xfffff, type 0x1b
			= DPL 0, pres 1, long 1, def32 0, gran 1
processor eflags	= interrupt enabled, resume, IOPL = 0
current process		= 0 (swapper)
[ thread pid 0 tid 100000 ]
Stopped at      __rw_rlock+0x23b:       movl    0x378(%r12),%eax
db> bt
Tracing pid 0 tid 100000 td 0xffffffff8150d370
__rw_rlock() at __rw_rlock+0x23b/frame 0xffffffff81843550
in_pcbpurgeif0() at in_pcbpurgeif0+0x30/frame 0xffffffff818435a0
in_ifdetach() at in_ifdetach+0x1c/frame 0xffffffff818435d0
if_detach() at if_detach+0x19b/frame 0xffffffff81843630
vtnet_attach() at vtnet_attach+0xb63/frame 0xffffffff81843760
device_attach() at device_attach+0x396/frame 0xffffffff818437b0
vtpci_probe_and_attach_child() at vtpci_probe_and_attach_child+0x91/frame 0xffffffff818437f0
vtpci_attach() at vtpci_attach+0x23b/frame 0xffffffff81843830
device_attach() at device_attach+0x396/frame 0xffffffff81843880
bus_generic_attach() at bus_generic_attach+0x4a/frame 0xffffffff818438a0
acpi_pci_attach() at acpi_pci_attach+0x15f/frame 0xffffffff818438f0
device_attach() at device_attach+0x396/frame 0xffffffff81843940
bus_generic_attach() at bus_generic_attach+0x4a/frame 0xffffffff81843960
acpi_pcib_attach() at acpi_pcib_attach+0x24d/frame 0xffffffff818439b0
acpi_pcib_acpi_attach() at acpi_pcib_acpi_attach+0x299/frame 0xffffffff81843a00
device_attach() at device_attach+0x396/frame 0xffffffff81843a50
bus_generic_attach() at bus_generic_attach+0x4a/frame 0xffffffff81843a70