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Date: Tue, 19 Jun 2007 16:04:16 +0200
From: Alexander Graf <agraf@suse.de>
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Subject: Re: [Qemu-devel] qemu-user mmap not thread-safe?
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To: qemu-devel@nongnu.org

Paul Brook wrote:
> On Thursday 24 May 2007, Alexander Graf wrote:
>   
>> Hi,
>>
>> while playing around with TLS on i386 i came across this problem which
>> occurs even when no TLS is used at all. If two threads just malloc()
>> memory all the time I get a segmentation fault after a short time. Might
>> this be a serious bug?
>>     
>
> qemu is not even vaguely threadsafe.
>
> Paul
>
>
>   
Hi,

I somehow narrowed the problem down to x86_64. As soon as I use
qemu-i386 on i386 or ppc the memory mapping tables are OK. When using
x86_64 as host they are broken. Could this be a generic 64-bit host
problem? I doubt that this actually has to do too much with the
threading itself, because it works fine on other platforms.

Alex