Hi, Reading Through
http://en.wikipedia.org/wiki/Amd64#FreeBSD under OpenBSD it says 2004. Complete in-tree support for the platform was achieved prior to the hardware's initial release due to AMD's loaning of several machines for the project's hackathon that year. OpenBSD developers have taken to the platform because of its use of the NX bit, which allowed for an easy implementation of the W^X feature. The code for the AMD64 port of OpenBSD also runs on the Intel processors with EM64T support which contain cloned support for the AMD64 extensions, but since Intel left out support for the page table NX bit in early EM64T processors, there is no W^X support on those Intel CPUs; later Intel EM64T processors added support for the NX bit under the name "XD bit". SMP is supported on OpenBSD's AMD64 port, starting with release 3.6 on November 1st, 200 ----------------------------------------------------------------------------------------------- Some time back Theo had mentioned in http://marc.theaimsgroup.com/?l=openbsd-misc&m=112260154519936&w=2 --------------------------------------------------------------------------------------------- Our W^X support is just as solid on i386 as it is on amd64, because on all our platforms we are very careful with the mapping of X and W objects. The i386 does fine. ------------------------------------------------------------------------------------------------- so does this mean that W^X support was available on EM64T processorseven before XD bit was added if you use OpenBSD? may be if it is true some one more knowledgeable can edit the wikipedia entry to make it clearer :-) Thankyou so much Kind Regards Siju