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Date: Tue, 16 Jul 2013 14:44:23 +0200
From: Jan Kiszka <jan.kiszka@siemens.com>
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Subject: Re: [Qemu-devel] [PATCH 06/22] memory: dispatch unassigned accesses
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To: Peter Maydell <peter.maydell@linaro.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>, "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>, Stefan Hajnoczi <stefanha@redhat.com>

On 2013-07-16 14:38, Peter Maydell wrote:
> On 16 July 2013 13:33, Paolo Bonzini <pbonzini@redhat.com> wrote:
>> Il 16/07/2013 14:28, Jan Kiszka ha scritto:
>>> This changed the value read from unassigned memory from -1 to 0. Any
>>> particular reason or an unintentional change?
>>
>> Cut-and-paste (unassigned RAM used to return 0, invalid MMIO used to
>> return -1, unifying the paths dropped the difference).
>>
>> I guess unassigned RAM can read as -1 just fine, so we can just change
>> unassigned_mem_read to return -1.
> 
> Behaviour for accesses to unassigned addresses should really
> be both bus and CPU specific...

Yes, that's what I was thinking as well when reading it. Still, lets
restore what we did before, then refine.

Jan

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