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From: "Dave Korn" <dave DOT korn AT artimi DOT com>
To: <cygwin AT cygwin DOT com>
Subject: RE: 1.7.0 CVS mmap failure
Date: Fri, 5 Jan 2007 18:47:16 -0000
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On 05 January 2007 18:42, Brian Ford wrote:

> On Fri, 5 Jan 2007, Corinna Vinschen wrote:
> 
>> In the failing case this should still work, since 0x7fff7000 + 0x9000
>> (36864 dec) == 0x80000000, so the mapping should fit into the usual 2
>> Gig address space.  Why Windows fails to do it, I have no idea.  The
>> error code 487 means invalid address which might mean "already taken"
>> address, but that's not visible in the strace.  To figure that out would
>> require to add a bit of VirtualQuery code to mmap and add appropriate
>> debug output.
> 
> I'm not quite sure exactly what this means, but I stumbled onto it in gdb:
> 
> (gdb) info w32 selector
> Selector $fs
> 0x03b: base=0x7fffe000 limit=0x00000fff 32-bit Data (Read/Write, Exp-up)
> Priviledge level = 3. Byte granular.
> 
> So, it does indeed look taken.


  Normally in windows you have the PEB and various TEBs living in that region.
I have no idea how this behaves on x64 or with /3gb, but it would seem that it
is still reserved.


    cheers,
      DaveK
-- 
Can't think of a witty .sigline today....


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