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Re: [Xen-devel] [RFC] x86: possible problem with guest_walk_tables()

To: Jan Beulich <JBeulich@xxxxxxxxxx>
Subject: Re: [Xen-devel] [RFC] x86: possible problem with guest_walk_tables()
From: Tim Deegan <Tim.Deegan@xxxxxxxxxx>
Date: Mon, 21 Mar 2011 13:57:48 +0000
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At 13:10 +0000 on 21 Mar (1300713029), Jan Beulich wrote:
> Yes, if this is really only GFN space, then it would "just" result in
> bad translations getting installed, possibly conflicting with others
> (e.g. in cache attributes).

Yep; that's no worse that anything else a guest can do. I'm pretty sure
no guest installs unaligned PAE entries and then tries to use them. (The
only case I _know_ of where the OS relies on h/w to enforce invalid-bit 
detection is Xen itself).

> Leaving aside the non-PAE case, does the fix presented look
> reasonable?
Yes, it looks correct to me.  Give me a Signed-off-by and I'll apply it. 



Tim Deegan <Tim.Deegan@xxxxxxxxxx>
Principal Software Engineer, Xen Platform Team
Citrix Systems UK Ltd.  (Company #02937203, SL9 0BG)

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