linux 3.13 guest crash with -cpu host

["Michael S. Tsirkin" <mst@redhat.com>]

I observe this with guest 3.13 and host 3.13
when running with -cpu host on my laptop:

[    0.043000] Call Trace:
[    0.043000]  [<ffffffff81d0e873>] init_hw_perf_events+0x33/0x5cd
[    0.043000]  [<ffffffff81d0e840>] ? check_bugs+0x40/0x40
[    0.043000]  [<ffffffff8100030a>] do_one_initcall+0x13a/0x190
[    0.043000]  [<ffffffff81d15133>] ?
native_smp_prepare_cpus+0x285/0x3ee
[    0.043000]  [<ffffffff81d068da>] kernel_init_freeable+0x136/0x298
[    0.043000]  [<ffffffff816834e0>] ? rest_init+0x80/0x80
[    0.043000]  [<ffffffff816834ee>] kernel_init+0xe/0x130
[    0.043000]  [<ffffffff8169422c>] ret_from_fork+0x7c/0xb0
[    0.043000]  [<ffffffff816834e0>] ? rest_init+0x80/0x80
[    0.043000] Code: 0f 46 c2 41 83 e8 01 89 05 63 4c fd ff 7e 2e 44 89
d2 b8 03 00 00 00 b9 45 03 00 00 83 e2 1f 83 fa 02 0f 4f c2 89 05 6d 4b
fd ff <0f> 32 48 c1 e2 20 89 c0 48 09 c2 48 89 15 0b 4c fd ff e8 c6 d3 
[    0.043000] RIP  [<ffffffff81d0f8c3>] intel_pmu_init+0x208/0x95a
[    0.043000]  RSP <ffff88003f25fe18>
[    0.043012] ---[ end trace 9f1576f03a80bfa0 ]---
[    0.044018] Kernel panic - not syncing: Attempted to kill init!
exitcode=0x0000000b

-cpu kvm64 works fine.

Reproduces with upstream qemu a75143eda2ddf581b51e96c000974bcdfe2cbd10,
as well as with qemu-kvm from Fedora 19.

Tried recent git from Linus - it still has this problem.

-- 
MST