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Re: [Xen-devel] cannot access memory beyond end of bootstrap direct-map

To: Pascal Bouchareine <pascal@xxxxxxxxx>, "xen-devel@xxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject: Re: [Xen-devel] cannot access memory beyond end of bootstrap direct-map area
From: Keir Fraser <keir.fraser@xxxxxxxxxxxxx>
Date: Thu, 27 Aug 2009 19:55:17 +0100
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On 27/08/2009 18:28, "Pascal Bouchareine" <pascal@xxxxxxxxx> wrote:

> Investigating the above message during xen 3.3 boot, found we left
> a wrong assumption [modules_length == (mod[n].end - mod[0].start)]
> in move_memory call, leading to an access above BOOTSTRAP_DIRECTMAP_END
> and this panic on x86_32.
> In my understanding Keir's patch 18630 was fixing this kind of problem
> and I'm wondering why this move_memory call didn't go away with it ?

Looks like a backporting mistake. The original bug didn't happen on my
system so the bad backport wasn't noticed.

> If this were ok, attached patch fixes the panic on my system.

You should be able to remove the bogus move_memory() call, and change
absolutely nothing else. Does that also work for you? That's the change I
would check in.

 -- Keir

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