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Re: [Xen-devel] [PATCH 01/17] x86: Make page cache mode a real type

On Fri, 31 Oct 2014, Borislav Petkov wrote:
> On Fri, Oct 31, 2014 at 03:00:17PM +0100, Juergen Gross wrote:
> > At the moment there are a lot of places that handle setting or getting
> > the page cache mode by treating the pgprot bits equal to the cache mode.
> > This is only true because there are a lot of assumptions about the setup
> > of the PAT MSR. Otherwise the cache type needs to get translated into
> > pgprot bits and vice versa.
> > 
> > This patch tries to prepare for that by introducing a separate type
> > for the cache mode and adding functions to translate between those and
> > pgprot values.
> > 
> > To avoid too much performance penalty the translation between cache mode
> > and pgprot values is done via tables which contain the relevant
> > information.  Write-back cache mode is hard-wired to be 0, all other
> > modes are configurable via those tables. For large pages there are
> > translation functions as the PAT bit is located at different positions
> > in the ptes of 4k and large pages.
> > 
> > Signed-off-by: Stefan Bader <stefan.bader@xxxxxxxxxxxxx>
> > Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
> Just a clarification question: how is one to understand this attribution
> here? Is Stefan the original author, was he a reviewer, or? Because this
> SOB chain is misleading...

Bah, wanted to ask that as well. Then got lost in the review and



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