Re: [PATCH] SUPPORT.md: extend security support for hosts to 12 TiB of memory

[Julien Grall <julien@xxxxxxx>]

Hi Jan,

On 06/04/2022 16:22, Jan Beulich wrote:
> On 06.04.2022 17:15, Julien Grall wrote:
> > On 06/04/2022 15:44, Jan Beulich wrote:
> > > c49ee0329ff3 ("SUPPORT.md: limit security support for hosts with very
> > > much memory"), as a result of XSA-385, restricted security support to
> > > 8 TiB of host memory. Extend this to 12 TiB, putting in place a guest
> > > restriction to 8 TiB in exchange.
> > And this is even without CONFIG_BIGMEM?
> Yes. BIGMEM only matters when memory extends past the 16 TiB boundary
> (i.e. when frame numbers with ore than 32 significant bits appear).
Thanks for the confirmation!

> > > --- a/SUPPORT.md
> > > +++ b/SUPPORT.md
> > > @@ -50,7 +50,7 @@ For the Cortex A57 r0p0 - r1p1, see Erra
> > >    
> > >    ### Physical Memory
> > >    
> > > -    Status: Supported up to 8 TiB
> > > +    Status: Supported up to 12 TiB
> > I am afraid this limit is going to be too high for Arm. Even the
> > previous one was technically incorrect. From [1], it should be:
> >     - 5TB for arm64
> >     - 16GB for arm32
> May I ask that you submit a patch correcting this, and I'll rebase
> on top of that? I can't really fit such an adjustment under the
> umbrella of the title and purpose of this change.
Sure. I will submit one soon.

Cheers,

--
Julien Grall