[OpenIndiana-discuss] KVM guests hang at boot on oi_151a4

[Aneurin Price]

Hello all,

I have a machine which was running some KVM guests successfully on
oi_151a3, but no longer since updating to oi_151a4.

I've tried a Windows 8 VM - when I connect to the qemu VNC display I
just get a black screen, which I believe indicates it's hanging at the
beginning of the Windows boot process. I've also tried booting
pxelinux - that successfully gets the boot image via TFTP, but hangs
immediately after that point. Both of these work fine with oi_151a3
using the same configuration.

When it happens, one CPU core is permanently pegged at 100%, and
kvmstat gives output like the following:

   pid vcpu |  exits :  haltx   irqx  irqwx    iox  mmiox |   irqs   emul   eptv
   757    0 | 396890 :      0      6     18     18      0 |     18      0      0
   757    1 |      0 :      0      0      0      0      0 |      0      0      0

Has anyone else seen anything like this?

I'm not certain what information I can provide which might be of
relevance, and I'm not sure what my next step should be in trying to
debug this; perhaps somebody can give me some pointers?

Thanks for your time,
Nye