DragonFly won't boot on qemu-kvm-1.0

[Emil Mikulic <emikulic@xxxxxxxxx>]

It works fine with -no-kvm, which is how I was able to update /usr/src
and build a new world and kernel (although it took >24h)

It's not http://bugs.dragonflybsd.org/issues/2328, I get the same
problem if I set hw.ioapic_enable=0

Boot looks like this:

DragonFly v3.3.0.2.g9b99c-DEVELOPMENT #0: Wed Oct 10 12:57:32 EST 2012
    root@:/usr/obj/usr/src/sys/X86_64_GENERIC
TSC clock: 2527114628 Hz, i8254 clock: 1193178 Hz
CPU: QEMU Virtual CPU version 1.0 (2527.15-MHz K8-class CPU)
  Origin = "GenuineIntel"  Id = 0x623  Stepping = 3
  Features=0x783fbfd<FPU,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,MMX,FXSR,SSE,SSE2>
  Features2=0x80002021<SSE3,VMX,CX16,VMM>
  AMD Features=0x20100800<SYSCALL,NX,LM>
  AMD Features2=0x1<LAHF>
real memory  = 1073333248 (1023 MB)
avail memory = 953683968 (909 MB)
lapic: divisor index 0, frequency 500005262 Hz
[...]
Mounting root from hammer:serno/QM00001.s1d
HAMMER(ROOT) recovery check seqno=00442467
HAMMER(ROOT) recovery range 3000000003848338-3000000003848338
HAMMER(ROOT) recovery nexto 3000000003848338 endseqno=00442468
HAMMER(ROOT) mounted clean, no recovery needed
DMA space used: 144k, remaining available: 16384k


Fatal trap 9: general protection fault while in kernel mode
cpuid = 0; lapic->id = 00000000
instruction pointer = 0x8:0xffffffff80898a02
stack pointer        = 0x10:0xffffffe00e457c00
frame pointer        = 0x10:0xffffffe003218bb0
code segment = base 0x0, limit 0xfffff, type 0x1b
= DPL 0, pres 1, long 0, def32 0, gran 1
processor eflags = interrupt enabled, IOPL = 0
current process = 1
current thread          = pri 10 (CRIT)
kernel: type 9 trap, code=0

CPU0 stopping CPUs: 0x00000000
 stopped
Stopped at      cpu_heavy_restore+0x72: movl    %ecx,%cr3
db> trace
cpu_heavy_restore() at cpu_heavy_restore+0x72 0xffffffff80898a02
tsleep() at tsleep+0x5ab 0xffffffff80509071
dfly_helper_thread() at dfly_helper_thread+0x324 0xffffffff804f7de5
db> show registers
cs                 0x8  gd_curthread
ss                0x10  gd_curthread+0x8
rax         0xffffffe00e465870
rcx         0x3dfdc007
rdx         0xffffffe00e457ce0
rbx         0xffffffff82248ae8  dfly_pcpu+0x8
rsp         0xffffffe00e457c10
rbp         0xffffffe003218bb0
rsi          0x349c000
rdi         0xffffffe00e465870
rip         0xffffffff80898a02  cpu_heavy_restore+0x72
rfl              0x202  gd_cnt+0x18e
r8          0xffffffff82249610  dfly_pcpu+0xb30
r9          0xfffffdff
r10                  0
r11         0xffffffff822490a0  dfly_pcpu+0x5c0
r12         0xffffffe00e465870
r13         0xffffffff82248ae8  dfly_pcpu+0x8
r14         0xffffffe00e465870
r15                  0
dr0                  0
dr1                  0
dr2                  0
dr3                  0
dr4         0xffff0ff0
dr5              0x400  gd_cnt+0x38c
dr6         0xffff0ff0
dr7              0x400  gd_cnt+0x38c
cpu_heavy_restore+0x72: movl    %ecx,%cr3
db>

What can I do to help diagnose this?