Re: [Qemu-devel] [PATCH] memory: make ram device read/write endian sensitive

[Peter Maydell]

On 23 February 2017 at 12:53, Paolo Bonzini <address@hidden> wrote:
>
>
> On 23/02/2017 13:26, Peter Maydell wrote:
>> On 23 February 2017 at 11:43, Paolo Bonzini <address@hidden> wrote:
>>> On 23/02/2017 12:34, Peter Maydell wrote:
>>>> We should probably update the doc comment to note that the
>>>> pointer is to host-endianness memory (and that this is not
>>>> like normal RAM which is target-endian)...
>>>
>>> I wouldn't call it host-endianness memory, and I disagree that normal
>>> RAM is target-endian---in both cases it's just a bunch of bytes.
>>>
>>> However, the access done by the MemoryRegionOps callbacks needs to match
>>> the endianness declared by the MemoryRegionOps themselves.
>>
>> Well, if the guest stores a bunch of integers to the memory, which
>> way round do you see them when you look at the bunch of bytes?
>
> You see them in whatever endianness the guest used.

I'm confused. I said "normal RAM and this ramdevice memory are
different", and you seem to be saying they're the same. I don't
think they are (in particular I think with a BE guest on an
LE host they'll look different).

thanks
-- PMM