This patch makes x86-64 compile in 2.5.5 and syncs it with changes in the i386
port. It also fixes some bugs that were discovered in recent testing:
- enhance 32bit emulation and fix bugs.
- fix security hole in vmalloc handling
- Do not use lockless gettimeofday for now because it is buggy.
The patch only changes x86_64 specific files.

-Andi