umass panic

[Eduardo Tongson]

on HEAD.
mounting a USB drive, detaching the drive, then unmounting it 
panics the system
. ..
umass0: Myson Century, Inc. USB Mass Storage Device, rev 2.00/b0.07, addr 2
da0 at umass-sim0 bus 0 target 0 lun 0
da0: <ST94811A  3.05> Fixed Direct Access SCSI-0 device 
da0: 1.000MB/s transfers
da0: 38154MB (78140160 512 byte sectors: 255H 63S/T 4864C)
. ..

Fatal trap 12: page fault while in kernel mode
fault virtual address = 0xc
fault code               = supervisor read, page not present
instruction pointer    = 0x8:0xc01476e6
stack pointer           = 0x10:0xcafae8ec
frame pointer          = 0x10:0xcafae8fc
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     = 751 (umount)
current thread       = pri 70 (CRIT)

kernel: type 12 trap, code=0


--ed 
Eduardo Tongson