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Re: [Xen-ia64-devel] Question: Special linux dom0 handling in vcpu_trans

To: Dietmar Hahn <dietmar.hahn@xxxxxxxxxxxxxxxxxxx>
Subject: Re: [Xen-ia64-devel] Question: Special linux dom0 handling in vcpu_translate()
From: tgingold@xxxxxxx
Date: Thu, 21 Jun 2007 09:49:50 +0200
Cc: Xen-ia64-devel <xen-ia64-devel@xxxxxxxxxxxxxxxxxxx>
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Quoting Dietmar Hahn <dietmar.hahn@xxxxxxxxxxxxxxxxxxx>:

> Hi,
> in vcpu_translate I found some lines of code which seems to be an
> optimization
> for the linux dom0:
> I found this, because mini-os uses the same scheme. Now the hypervisor does
> the itc for mini-os with a linux kernel identity mapped pte!
> In general this may leads to problems if other systems with similar region
> scheme are running on xen.
> In particular I have here the problem that using protection keys for such
> addresses is impossible!
> Is it possible to do this optimization for the linux kernel another way?

I think this special linux optimization should be enabled by the OS. We should
add an hypercall (or a SAL call) for this.


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