I got a kernel panic in my domU (3.0_BETA). dom0 is NetBSd 3.0_BETA.

ROOT xenU:~> halt -p
Jun 17 12:50:11 xenU halt: halted by root
Jun 17 12:50:11 xenU syslogd: Exiting on signal 15
uvm_fault(0xc9be81c0, 0, 0, 1) -> 0xe
kernel: page fault trap, code=0
Stopped in pid 360.1 (bash) at  netbsd:spec_ioctl+0xe:  movl 
0xc(%eax),%esi
spec_ioctl(ca517d84,ca517da4,9bec3,0,c037bb80) at netbsd:spec_ioctl+0xe
VOP_IOCTL(ca8a6360,80047476,ca517ea4,3,c9be00fc) at netbsd:VOP_IOCTL+0x40
vn_ioctl(c9bf4038,80047476,ca517ea4,c9be2b28,0) at netbsd:vn_ioctl+0x9e
sys_ioctl(c9beb39c,ca517f64,ca517f5c,0,c0331eb9) at netbsd:sys_ioctl+0x12e
syscall_plain() at netbsd:syscall_plain+0x18f
--- syscall (number 54) ---
0xbdbbfc87:
ds          0x11
es          0x11
fs          0x31
gs          0x11
edi         0
esi         0xca8a6360
ebp         0xca517d6c
ebx         0xca517d84
edx         0xca8a6360
ecx         0xc9bf4038
eax         0
eip         0xc02d287a  spec_ioctl+0xe
cs          0x9
eflags      0x10286
esp         0xca517d64
ss          0x11
netbsd:spec_ioctl+0xe:  movl    0xc(%eax),%esi
Stopped in pid 360.1 (bash) at  netbsd:spec_ioctl+0xe:  movl 
0xc(%eax),%esi
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