From mboxrd@z Thu Jan  1 00:00:00 1970
From: Richard Henderson <rth@twiddle.net>
Subject: Re: [PATCH] memory: use signed arithmetic
Date: Tue, 02 Aug 2011 15:15:25 -0700
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Cc: Jan Kiszka <jan.kiszka@siemens.com>, qemu-devel@nongnu.org,
	kvm@vger.kernel.org
To: Avi Kivity <avi@redhat.com>
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On 08/02/2011 03:06 PM, Avi Kivity wrote:
> I don't think there's any cpu which has a real 64-bit physical
> address space? Don't they all truncate it?

I don't know.  You're right that x86_64 does, at 48 bits.
The alpha system I'm trying to emulate does, at 50 bits.

I guess if IBM agrees wrt p-series and z-series emulation, then
I'd be ok, so long as you add a comment above that structure that
says no existing hw implementation actually uses 63 address bits.


r~