[PANIC] after manually issuing 'ifconfig sf0'

[David O'Brien]

Machine booted, without any mention of sf(4) in rc.conf or loader.conf and
without sf(4) in the core kernel.  This is without WITNESS or INVARIANTS.

>From multi-user, I issued 'ifconfig sf0' and got the below panic.
These are the console messages related to this:


FreeBSD 9.0-CURRENT #654 r215604M: Sat Nov 20 19:51:27 PST 2010
    rootk at dragon:/sys/i386/compile/DRAGON i386
[..]
Thu Dec  2 09:33:50 PST 2010
sf0: <Adaptec ANA-62044 (rev 1) 10/100BaseTX> port 0x5000-0x50ff mem 0xb0400000-0xb047ffff irq 19 at device 4.0 on pci5
miibus2: <MII bus> on sf0
ukphy0: <Generic IEEE 802.3u media interface> PHY 1 on miibus2
ukphy0:  10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto
sf0: Ethernet address: 00:00:d1:ed:81:95
sf1: <Adaptec ANA-62044 (rev 1) 10/100BaseTX> port 0x5400-0x54ff mem 0xb0480000-0xb04fffff irq 16 at device 5.0 on pci5
miibus3: <MII bus> on sf1
ukphy1: <Generic IEEE 802.3u media interface> PHY 1 on miibus3
ukphy1:  10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto
sf1: Ethernet address: 00:00:d1:ed:81:96
sf2: <Adaptec ANA-62044 (rev 1) 10/100BaseTX> port 0x5800-0x58ff mem 0xb0500000-0xb057ffff irq 18 at device 6.0 on pci5
miibus4: <MII bus> on sf2
ukphy2: <Generic IEEE 802.3u media interface> PHY 1 on miibus4
ukphy2:  10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto
sf2: Ethernet address: 00:00:d1:ed:81:97
sf3: <Adaptec ANA-62044 (rev 1) 10/100BaseTX> port 0x5c00-0x5cff mem 0xb0580000-0xb05fffff irq 17 at device 7.0 on pci5
miibus5: <MII bus> on sf3
ukphy3: <Generic IEEE 802.3u media interface> PHY 1 on miibus5
ukphy3:  10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto
sf3: Ethernet address: 00:00:d1:ed:81:98


Fatal trap 12: page fault while in kernel mode
cpuid = 0; apic id = 00
fault virtual address	= 0x238
fault code		= supervisor read, page not present
instruction pointer	= 0x20:0xc05be315
stack pointer	        = 0x28:0xe7a5eab4
frame pointer	        = 0x28:0xe7a5eaf4
code segment		= base 0x0, limit 0xfffff, type 0x1b
			= DPL 0, pres 1, def32 1, gran 1
processor eflags	= interrupt enabled, resume, IOPL = 0
current process		= 2590 (mail.local)
trap number		= 12
panic: page fault
cpuid = 0
KDB: stack backtrace:
db_trace_self_wrapper(c0839222,d31206e,2c66000a,70797420,78302065,...) at 0xc04e9ab6 = db_trace_self_wrapper+0x26
kdb_backtrace(c0857e2a,0,c0822eb2,e7a5e910,0,...) at 0xc05fa2fa = kdb_backtrace+0x2a
panic(c0822eb2,c0858b68,c59aea18,1,1,...) at 0xc05cd297 = panic+0x117
trap_fatal(c596d880,0,c0858a20,36b,238,...) at 0xc07dcd65 = trap_fatal+0x325
trap_pfault(e7a5e9b8,c07fae4d,e7a5e9cc,0,c59ae870,...) at 0xc07dcf40 = trap_pfault+0x1c0
trap(e7a5ea74) at 0xc07dd5f5 = trap+0x5d5
calltrap() at 0xc07c8dfc = calltrap+0x6
--- trap 0xc, eip = 0xc05be315, esp = 0xe7a5eab4, ebp = 0xe7a5eaf4 ---
_mtx_lock_sleep(c51b8be8,c59ae870,0,c08501a2,a43,...) at 0xc05be315 = _mtx_lock_sleep+0xa5
_mtx_lock_flags(c51b8be8,0,c08501a2,a43,c51b8c1c,...) at 0xc05be542 = _mtx_lock_flags+0x42
uma_zfree_arg(c51b8c08,c6555000,c6554000,0,e7a5eb80,...) at 0xc0790958 = uma_zfree_arg+0xd8
free(c6555000,c0886600,e7a5ec24,c6eb39a0,e7a5ec24,...) at 0xc05bb61e = free+0xae
random_read(c5283700,e7a5ec24,0,0,0,...) at 0xc0c3535e = random_read+0x9e
devfs_read_f(c6eb39a0,e7a5ec24,c5157580,0,c59ae870,...) at 0xc056bd32 = devfs_read_f+0x82
dofileread(e7a5ec24,ffffffff,ffffffff,0,c6eb39a0,...) at 0xc060adbe = dofileread+0x9e
kern_readv(c59ae870,4,e7a5ec24,e7a5ec44,1,...) at 0xc060b148 = kern_readv+0x58
read(c59ae870,e7a5ecec,c59ae870,e7a5ed28,6,...) at 0xc060b23f = read+0x4f
syscallenter(c59ae870,e7a5ece4,e7a5ece4,0,3,...) at 0xc0605d43 = syscallenter+0x2c3
syscall(e7a5ed28) at 0xc07dcf94 = syscall+0x34
Xint0x80_syscall() at 0xc07c8e91 = Xint0x80_syscall+0x21
--- syscall (3, FreeBSD ELF32, read), eip = 0x2819762b, esp = 0xbfbfdf6c, ebp = 0xbfbfe028 ---
Uptime: 6m26s
Physical memory: 2034 MB
Dumping 111 MB: