[PATCH] KVM: PPC: Book3s PR: Allow access to unprivileged MMCR2 register

[Paul Mackerras]

On Wed, Sep 21, 2016 at 03:06:45PM +0200, Thomas Huth wrote:
> The MMCR2 register is available twice, one time with number 785
> (privileged access), and one time with number 769 (unprivileged,
> but it can be disabled completely). In former times, the Linux
> kernel was using the unprivileged register 769 only, but since
> commit 8dd75ccb571f3c92c ("powerpc: Use privileged SPR number
> for MMCR2"), it uses the privileged register 785 instead.
> The KVM-PR code then of course also switched to use the SPR 785,
> but this is causing older guest kernels to crash, since these
> kernels still access 769 instead. So to support older kernels
> with KVM-PR again, we have to support register 769 in KVM-PR, too.
> 
> Fixes: 8dd75ccb571f3c92c48014b3dabd3d51a115ab41
> Cc: stable at vger.kernel.org # v3.10+
> Signed-off-by: Thomas Huth <thuth at redhat.com>

Thanks, applied to kvm-ppc-next.

Paul.