Re: [Qemu-devel] [PATCH] memory: simple memory tree printer

[Jan Kiszka <jan.kiszka@siemens.com>]

On 2011-09-12 11:11, Avi Kivity wrote:
> On 09/12/2011 12:01 PM, Jan Kiszka wrote:
>> On 2011-09-12 08:43, Richard Henderson wrote:
>>>  On 09/11/2011 09:31 PM, Blue Swirl wrote:
>>>>  Field 'offset' is always zero, maybe that is not interesting. Will it
>>>>  become one day?
>>>
>>>  It's not always zero, but only used by certain devices.
>>
>> I do not see any users, neither upstream nor in Avi's tree.
> 
> There aren't.
> 
>> To my (semi-)understanding, offset should correlate to region_offset of
>> cpu_register_physical_memory_offset: legacy device models require this
>> to be 0 as they expect an absolute memory address passed to their
>> handler, in contrast to a normal one that is relative to the regions
>> base. But I do not see how the memory region offset actually helps here.
>>
> 
> mr->offset is added to the address in memory_region_{read,write}_thunk_n().

Ah, ok.

So the default address passed to the handler is now already relative? I
think we should keep it like this for all converted devices, ie. take
the chance, fix the remaining models, and drop the offset.

Jan

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