Re: [PATCH 10/16] x86/mm/pti: Populate valid user pud entries

From: Joerg Roedel
Date: Tue Jan 16 2018 - 14:41:19 EST


On Tue, Jan 16, 2018 at 10:06:48AM -0800, Dave Hansen wrote:
> On 01/16/2018 08:36 AM, Joerg Roedel wrote:
> >
> > In PAE page-tables at the top-level most bits we usually set
> > with _KERNPG_TABLE are reserved, resulting in a #GP when
> > they are loaded by the processor.
>
> Can you save me the trip to the SDM and remind me which bits actually
> cause trouble here?

Everything besides PRESENT, PCD, PWT and the actual physical address, so
RW, and NX for example cause a #GP.


Joerg