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Subject: Re: [Qemu-devel] [PATCH 2/9] alpha-linux-user: Work around hosted
 mmap allocation problems
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To: Alexander Graf <agraf@suse.de>
Cc: Peter Maydell <peter.maydell@linaro.org>, Paul Brook <paul@codesourcery.com>, Riku Voipio <riku.voipio@iki.fi>, "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>, =?UTF-8?B?QW5kcmVhcyBGw6RyYmVy?= <afaerber@suse.de>

On 2012-06-12 07:53, Alexander Graf wrote:
> 
> 
> On 12.06.2012, at 16:27, Richard Henderson <rth@twiddle.net> wrote:
> 
>> On 2012-06-12 07:12, Andreas Färber wrote:
>>> This looks fishy to me... why should the kernel use a bigger address
>>> space than hardware? For arm on x86_64 such a workaround was not
>>> necessary iirc.
>>
>> I can tell you what I observe.  That with a certain sequence of
>> allocations the x86_64 kernel will quit accepting an address "near"
>> (1<<38) as a hint for where to allocate memory and begin returning
>> an addresses near (1<<48).  
> 
> Hrm, does -R work for you? :)

Lol.

Actually I've tried it a couple of times: -R 32G.  And, no, it 
doesn't work very well.  ;-)


r~