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Re: [PATCH 02/17] x86: split __{get,put}_user() into "guest" and "unsafe" variants


  • To: Jan Beulich <jbeulich@xxxxxxxx>
  • From: Roger Pau Monné <roger.pau@xxxxxxxxxx>
  • Date: Tue, 9 Feb 2021 16:23:55 +0100
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On Tue, Feb 09, 2021 at 03:57:22PM +0100, Jan Beulich wrote:
> I did change the paragraph to read
> 
> The "guest" variants are intended to work with (potentially) fully guest
> controlled addresses, while the "unsafe" variants are intended to be
> used in order to access addresses not (directly) under guest control,
> within Xen's part of virtual address space. (For linear page table and
> descriptor table accesses the low bits of the addresses may still be
> guest controlled, but this still won't allow speculation to "escape"
> into unwanted areas.) Subsequently we will want them to have distinct
> behavior, so as first step identify which one is which. For now, both
> groups of constructs alias one another.
> 
> earlier today. Is this clear enough? Relevant parts I've also mirrored
> into patch 3's description?

Yes, that does indeed seem clearer, thanks.

Roger.



 


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