Re: [PATCH v9 12/26] x86/fpu/xstate: Use feature disable (XFD) to protect dynamic user state

From: Len Brown
Date: Tue Aug 31 2021 - 18:44:45 EST


On Tue, Aug 31, 2021 at 6:39 PM Thiago Macieira
<thiago.macieira@xxxxxxxxx> wrote:
>
> On Tuesday, 31 August 2021 15:15:55 PDT Len Brown wrote:
> > Indeed, I believe that there is universal agreement that a synchronous
> > return code
> > from a system call is a far superior programming model than decoding
> > the location of a failure in a system call. (no, the IP isn't random -- it
> > is always the 1st instruction in that thread to touch a TMM register).
>
> That instruction is actually likely going to be a memory load, probably an
> LDTILECFG.

There is no fault on LDTILECONFIG, it will occur on the load tile data.
But yes, still a memory load (with a TMM destination)

Len Brown, Intel Open Source Technology Center