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Date: Wed, 31 Dec 2014 20:32:59 +0100
From: Laszlo Ersek <lersek@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH] fw_cfg: fix endianness in
	fw_cfg_data_mem_read() / _write()
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Maydell <peter.maydell@linaro.org>, Drew Jones <drjones@redhat.com>, Gerd Hoffmann <kraxel@redhat.com>, Alexander Graf <agraf@suse.de>, qemu devel list <qemu-devel@nongnu.org>

On 12/31/14 20:25, Paolo Bonzini wrote:
> 
> 
> On 31/12/2014 18:29, Peter Maydell wrote:
>> On 31 December 2014 at 16:23, Paolo Bonzini <pbonzini@redhat.com> wrote:
>>> $ arm-softmmu/qemu-system-arm -M virt -machine accel=qtest \
>>>              -qtest stdio -uuid 4600cb32-38ec-4b2f-8acb-81c6ea54f2d8
>>> writew 0x9020008 0x0200
>>> readl 0x9020000
>>>
>>> The readl should return "OK 0x000000004600cb32".
>>
>> On BE ppc64 host I get:
>> OK 0x0000000032cb0046
>> with or without Laszlo's patch.
>>
>> On LE x86-64 host I get
>> OK 0x000000004600cb32
>> without the patch, and
>> OK 0x0000000032cb0046
>> with it.
>>
>> So I think that the patch is good (in that it removes a host-endian
>> dependency which we should not have) and your intuition for the
>> correct result is possibly not so good :-)
> 
> Indeed.  I give up until at least the end of the holiday break.

I disagree with the wording "give up". I owe you a great deal of
gratitude for the technical advice and the time & attention you've spent
helping me with this. I hope I can reciprocate sometime.

Laszlo