[patch 00/11] PAT x86: PAT support for x86

[venkatesh.pallipadi@intel.com]

This series is heavily derived from the PAT patchset by Eric Biederman and
Andi Kleen.
http://www.firstfloor.org/pub/ak/x86_64/pat/

This patchset is a followup of "PAT support for X86_64"
http://www.ussg.iu.edu/hypermail/linux/kernel/0712.1/2268.html

Things changed from the above (Dec 13 2007) version:
* PAT mappings now used are - (0,WB) (1,WT) (2,WC) (3,UC).
* Covers both i386 and x86_64.
* Resolve the /sysfs issue by exporting wc and uc interfaces.
* Piggyback PAT initialization on existing MTRR initialization as they
  have same setup rules.
* Avoid early table allocation problem for x86_64 by doing the reserved
  region pruning later in the boot. Handle both memory identity mapping and
  kernel test mapping.
* Handle fork() and /dev/mem mapping and unmapping cases.

Patchset is against Ingo's x86 branch from 2 days ago. Will need some merging
effort with Andi's CPA changes and few other changes like pgtable.h unification.

Not mapping reserved region in identity map is a sort of big change that can
potentially have side-effects on drivers (especially on x86_64), that
assume entire address range is mapped in identity map and use __va to
access reserved regions instead of ioremap/early_ioremap. We have
changed few such common cases, but there can be more in /drivers land.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>

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