Re: [Qemu-devel] qemu-system-ppc64 hanging occasionally in disk writes

[Richard W.M. Jones]

On Thu, Jun 28, 2012 at 04:25:26PM +0200, Alexander Graf wrote:
> On 06/15/2012 12:01 AM, Richard W.M. Jones wrote:
> >On Thu, Jun 14, 2012 at 11:34:37PM +0200, Alexander Graf wrote:
> >>>/home/rjones/d/qemu/ppc64-softmmu/qemu-system-ppc64 \
> >>>    -global virtio-blk-pci.scsi=off \
> >>>    -nodefconfig \
> >>>    -nodefaults \
> >>>    -nographic \
> >>>    -device virtio-scsi-pci,id=scsi \
> >>>    -drive file=test1.img,cache=off,format=raw,id=hd0,if=none \
> >>>    -device scsi-hd,drive=hd0 \
> >>Don't you have to specify bus= too?
> >I don't know.  The identical command line works on x86-64, but I
> >don't know if it's correct.
> >
> >BTW KVM PR now boots the firmware, but fails when it tries to boot our
> >(Fedora) guest kernel because of missing emulation of 'ldx':
> >
> >[764597.404573] Couldn't emulate instruction 0x7fb6502a (op 31 xop 21)
> >[764597.404583] kvmppc_emulate_mmio: emulation failed (7fb6502a)
> >[768211.269020] Couldn't emulate instruction 0x7fb6502a (op 31 xop 21)
> >[768211.269029] kvmppc_emulate_mmio: emulation failed (7fb6502a)
> >
> >I will try to see if I can fix this and submit a patch if I'm
> >successful.
> 
> Ugh. Mind to give me a link to your Fedora kernel, so I can check
> out what it's doing? MMIO with 64 bit instructions is slightly
> unusual and rather points to a different error :).

So that bug went away when I recompiled my kernel from source.  No
idea why that happened, but it made me less interested in fixing the
emulation bug.

However here are the Fedora ppc64 kernels:

  http://ppc.koji.fedoraproject.org/koji/packageinfo?packageID=3142

I'm not 100% sure now exactly which of the (.fc17) kernels I was
using.  I think it was probably this one:

  http://ppc.koji.fedoraproject.org/koji/buildinfo?buildID=84349
  - kernel-3.3.4-5.fc17.ppc64

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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