i386 and PAE NX (continued)


We could use PAE NX to support W^X on some i386 machines

Two weeks ago: Integrated PAE code into OpenBSD.

Not a compile option!
Code is always included in the kernel
Kernel decides to switch to PAE mode, during boot sequence
Decision based on lots of phys memory?  to use PAE NX bit? etc

But... there are issues:

PAE is slower
Uses more than 2x as much kernel memory

PAE NX does per-page W^X... but line-in-the-sand is normally enough