mpt(4) causes panic at boot

I'm running 7.0-BETA4 on an IBM x3550 with amd64. It panics at
half way of boot:

Fatal trap 12: page fault while in kernel mode
cpuid = 0; apic id = 00
fault virtual address   = 0x258
fault code              = supervisor read data, page not present
instruction pointer     = 0x8:0xffffffff80478e2e
stack pointer           = 0x10:0xffffffffac2ccbb0
frame pointer           = 0x10:0xffffffffac2ccbd0
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         = 30 (mpt_recovery0)
[thread pid 30 tid 100022 ]
Stopped at      _mtx_lock_sleep+0x4e:   movl    0x258(%rcx),%esi
db> tr
Tracing pid 30 tid 100022 td 0xffffff0001121340
_mtx_lock_sleep() at _mtx_lock_sleep+0x4e
mpt_recovery_thread() at mpt_recovery_thread+0x35b
fork_exit() at fork_exit+0x11f
fork_trampoline() at fork_trampoline+0xe
--- trap 0, rip = 0, rsp = 0xffffffffac2ccd30, rbp = 0 ---

The mpt does not attach correctly (it's same in 6.x but it boots fine).
Relevant dmesg:

mpt0: <LSILogic 1030 Ultra4 Adapter> port 0x5000-0x50ff mem
0xc6ff0000-0xc6ffffff,0xc6fe0000-0xc6feffff irq 24 at device 1.0 on
pci20
mpt0: Reserved 0x100 bytes for rid 0x10 type 4 at 0x5000
mpt0: Reserved 0x10000 bytes for rid 0x14 type 3 at 0xc6ff0000
ioapic1: routing intpin 0 (PCI IRQ 24) to vector 49
mpt0: [MPSAFE]
mpt0: [ITHREAD]
mpt0: MPI Version=1.2.14.0
mpt0: Capabilities: ( RAID-1E RAID-1 SAFTE )
mpt0: 0 Active Volumes (1 Max)
mpt0: 0 Hidden Drive Members (6 Max)
mpt0: mpt_wait_req(6) timed out
mpt0: port 0 enable timed out
mpt0: failed to enable port 0
mpt0: personality mpt_core attached but would not enable (6)

Full boot log can be found at

http://rafb.net/p/kuLZOo82.html

Any ideas what happens?

Thanks,
Rong-En Fan