NX bit emulation

[mrn]

Hi,
Could someone explain to me how the NX bit can be emulated on platforms such as 32-bit x86 where the hardware doesn't provide it? I would be greatful for an explanation of the basics of the way it is emulated since I simply can't imagine how it could be realized. Thanks in advance.

[Brynet-Inc]

It's possible to use segmentation to achieve a similar effect, as a sort of line in the sand.. executable area up until some point and then non-executable data.

I believe that's how a lot of x86 OS's are implementing it these days, at least OpenBSD and Linux.

[mrn]

Thanks for the reply. I guess you were right it can be done using segmentation. Following links on http://stackoverflow.com/questions/4703 ... -emulation I found out NX emulation can as well be done using TLB.