Re: [PATCH v4.14 3/4] KVM: PPC: Book3S HV: Fix VRMA initialization with 2MB or 1GB memory backing

[Greg KH <greg@kroah.com>]

On Fri, May 11, 2018 at 04:20:58PM +1000, Paul Mackerras wrote:
> commit debd574f4195e205ba505b25e19b2b797f4bcd94 upstream.
> 
> The current code for initializing the VRMA (virtual real memory area)
> for HPT guests requires the page size of the backing memory to be one
> of 4kB, 64kB or 16MB.  With a radix host we have the possibility that
> the backing memory page size can be 2MB or 1GB.  In these cases, if the
> guest switches to HPT mode, KVM will not initialize the VRMA and the
> guest will fail to run.
> 
> In fact it is not necessary that the VRMA page size is the same as the
> backing memory page size; any VRMA page size less than or equal to the
> backing memory page size is acceptable.  Therefore we now choose the
> largest page size out of the set {4k, 64k, 16M} which is not larger
> than the backing memory page size.
> 
> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
> ---
>  arch/powerpc/kvm/book3s_hv.c | 12 +++++++-----
>  1 file changed, 7 insertions(+), 5 deletions(-)

Applied, thanks.

greg k-h