uma panic while unloading sbp.ko

[Marc UBM Bocklet]

Hiho! :-)

I encountered a non-repeatable panic with

FreeBSD greatsheep 6.0-STABLE FreeBSD 6.0-STABLE #4: Sun Jan 15 16:13:56
CET 200 6     sheep at greatsheep:/usr/obj/usr/src/sys/SUBMARINE_SMP  i386

System was built at the end of november 2005.


The panic:

sbp0: detached


Fatal trap 12: page fault while in kernel mode
cpuid = 0; apic id = 00
fault virtual address   = 0x15
fault code              = supervisor read, page not present
instruction pointer     = 0x20:0xc0759760
stack pointer           = 0x28:0xdacd7bc8
frame pointer           = 0x28:0xdacd7be8
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         = 3168 (kldunload)


Backtrace:

Tracing pid 3168 tid 100195 td 0xc41cf960
uma_zfree_internal(c1061960,c32ef400,0,1,3,0,c106c8c0,dacd7c60) at
uma_zfree_internal+0x120 uma_zfree_arg(c1061960,c32ef400,0,c0807c76,0)
at uma_zfree_arg+0x3ea
malloc_uninit(c0993100,c0807c76,dacd7c5c,dacd7c60,0) at
malloc_uninit+0x109
linker_file_sysuninit(c32e4600,c0846120,0,c3d01100,0) at
linker_file_sysuninit+0xa0
linker_file_unload(c32e4600,0,dacd7cd0,c05fa4f8,c41cf960) at
linker_file_unload+0x144 kern_kldunload(c41cf960,7,0,dacd7d30,c07c2310)
at kern_kldunload+0xd2 kldunloadf(c41cf960,dacd7d04,8,c41cf960,4) at
kldunloadf+0x2c syscall(3b,3b,3b,7,bfbfee72) at syscall+0x380
Xint0x80_syscall() at Xint0x80_syscall+0x1f
--- syscall (444, FreeBSD ELF32, kldunloadf), eip = 0x280ba877, esp =
0xbfbfe90c, ebp = 0xbfbfed78 ---


What I did:

Connect a non-working external firewire hdd-case to my firewire pci
card. Disconnected it. Unloaded sbp.ko (no device was registered, as
the stupid case is obviously broken) and my system panicked.

Further debug information is attached (show uma, show threads).

Thanks in advance for your help :-)


Bye
Marc


-- 
"And what rough beast, its hour come round at last,
Slouches towards Bethlehem to be born?"

W.B. Yeats, The Second Coming