Re: [PATCH v2] kvm: arm64: vgic: fix hyp panic with 64k pages on juno platform

[Will Deacon <will.deacon@arm.com>]

On Fri, Jul 25, 2014 at 05:24:18PM +0100, Joel Schopp wrote:
> 
> On 07/25/2014 11:02 AM, Peter Maydell wrote:
> > On 25 July 2014 16:56, Joel Schopp <joel.schopp@amd.com> wrote:
> >> The problem with this patch is the gicv is really 8K.  The reason you
> >> would map at a 60K offset (0xf000), and why we do on our SOC, is so that
> >> the 8K gicv would pick up the last 4K from the first page and the first
> >> 4K from the next page.  With your patch it is impossible to map all 8K
> >> of the gicv with 64K pages.
> >>
> >> My SOC which works fine with kvm now will go to not working with kvm
> >> after this patch.
> > Your SOC currently works by fluke because the guest doesn't
> > look at the last 4K of the GICC. If you're happy with it continuing
> > to work by fluke you could make your device tree say it had a
> > 64K GICV region with a 64K-aligned base.
> >
> > To make it work not by fluke but actually correctly requires
> > Marc's patchset, at a minimum.
> 
> Since we aren't actually using the last 4K of the gicv at the moment I
> supppose I could drop my objections to this patch and change my device
> tree until Marc's patchset provides a proper solution for the gicv's
> second 4K that works for everybody.
> 
> Acked-by: Joel Schopp <joel.schopp@amd.com>

Thanks, Joel.

Will