Re: [Qemu-devel] Re: [PATCH 2/6] Use correct types to enable > 2G support (v2)

[Avi Kivity <avi@qumranet.com>]

Paul Brook wrote:
> On Sunday 10 February 2008, Avi Kivity wrote:
>   
>> Paul Brook wrote:
>>     
>>>>> as far as i remember it was used to address something with
>>>>> cpu_physical_memory_rw() probably related to &TARGET_PAGE_SIZE
>>>>> or ~TARGET_PAGE_SIZE,
>>>>>
>>>>> the fact is that i dont know if it ever fixed anything
>>>>>           
>>>> It fixes TARGET_PAGE_MASK, defined one line downscreen.
>>>>         
>>> That doesn't really answer the question. What was wrong with the original
>>> definition?
>>>       
>> There are many instances of ((physical address) & TARGET_PAGE_MASK)
>> scattered throughout the code.  With 64-bit physical addresses, this
>> causes truncation.
>>     
>
> No it doesn't. TARGET_PAGE_MASK will be sign extended to the width of 
> physical_address. This is why I asked for a concrete example of something 
> that broke.
>   

I understand now.  No, I don't recall a specific instance, and it may 
have been an unnecessary step along the way to get large memory support 
working.

-- 
error compiling committee.c: too many arguments to function


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