oops to zero

>
> On Oct 6, 2007, at 15:08 , David T. Lewis wrote:
>
> >Actually the Unix VM already does use mmap() on /dev/zero to obtain  
> >the
> >base address, so it is easy to request a specific base address. Ian  
> >pointed
> >this out to me when I was doing the "32bit clean" patches, and that is
> >how I was able to test those changes.
> >
> >The attached diff shows where to make the change in sqUnixMemory.c.
> >
> >Note that mmap() will assign its own address if it does not agree with
> >the one that you requested. You will need to pick an address that  
> >works
> >on various versions of the kernel, and on both 32 bit and 64 bit  
> >systems
> >(or perhaps provide a list of addresses, and let the VM find one that
> >works on that particular platform).  The value 0x4000000 seems  
> >reasonable
> >on a 64 bit AMD Linux 2.6 system, but I did not check to see if it  
> >works
> >on a 32 bit system, so you may need to experiment a bit.
> >
> >The OLPC platform has well defined hardware and OS, so it would be  
> >good
> >to pick a number that works on OLPC and make that the default.
>
> Interesting - I also found that on Linux I can modify the executable  
> to disable randomization using the -R flag of setarch:
>
> http://www.linuxcommand.org/man_pages/setarch8.html
>
> Have not tested this yet. And does the image loading logic actually  
> check if a remap is necessary?