It comes from the early x86 processors not having an "no-execute" permission bit... | Hacker News

Hacker News new | past | comments | ask | show | jobs | submit

login

pkaye on Jan 14, 2015 | parent | context | favorite | on: OpenBSD's kernel gets W^X treatment

It comes from the early x86 processors not having an "no-execute" permission bit for page table entries. In the AMD64 bit architecture, an NX bit was added.

danieldk on Jan 14, 2015 [–]

And Intel retroactively added it to x86 (requiring PAE). E.g.:

http://ark.intel.com/products/27460/Intel-Pentium-4-Processo...

brynet on Jan 14, 2015 | [–]

Mike Larkin made a follow-up post to the mailing lists mentioning some upcoming work.

http://marc.info/?l=openbsd-tech&m=142122093110713&w=2

OpenBSD/i386 still has to run on systems without PAE, but it should also take advantage of the capabilities of modern processors.

Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact