This is a note to let you know that I've just added the patch titled

    mm: clear pmd_numa before invalidating

to the 3.10-stable tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     mm-clear-pmd_numa-before-invalidating.patch
and it can be found in the queue-3.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From 67f87463d3a3362424efcbe8b40e4772fd34fc61 Mon Sep 17 00:00:00 2001
From: Mel Gorman <[email protected]>
Date: Wed, 18 Dec 2013 17:08:34 -0800
Subject: mm: clear pmd_numa before invalidating

From: Mel Gorman <[email protected]>

commit 67f87463d3a3362424efcbe8b40e4772fd34fc61 upstream.

On x86, PMD entries are similar to _PAGE_PROTNONE protection and are
handled as NUMA hinting faults.  The following two page table protection
bits are what defines them

        _PAGE_NUMA:set  _PAGE_PRESENT:clear

A PMD is considered present if any of the _PAGE_PRESENT, _PAGE_PROTNONE,
_PAGE_PSE or _PAGE_NUMA bits are set.  If pmdp_invalidate encounters a
pmd_numa, it clears the present bit leaving _PAGE_NUMA which will be
considered not present by the CPU but present by pmd_present.  The
existing caller of pmdp_invalidate should handle it but it's an
inconsistent state for a PMD.  This patch keeps the state consistent
when calling pmdp_invalidate.

Signed-off-by: Mel Gorman <[email protected]>
Reviewed-by: Rik van Riel <[email protected]>
Cc: Alex Thorlton <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 mm/pgtable-generic.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/mm/pgtable-generic.c
+++ b/mm/pgtable-generic.c
@@ -166,6 +166,9 @@ pgtable_t pgtable_trans_huge_withdraw(st
 void pmdp_invalidate(struct vm_area_struct *vma, unsigned long address,
                     pmd_t *pmdp)
 {
+       pmd_t entry = *pmdp;
+       if (pmd_numa(entry))
+               entry = pmd_mknonnuma(entry);
        set_pmd_at(vma->vm_mm, address, pmdp, pmd_mknotpresent(*pmdp));
        flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
 }


Patches currently in stable-queue which might be from [email protected] are

queue-3.10/sched-numa-skip-inaccessible-vmas.patch
queue-3.10/mm-clear-pmd_numa-before-invalidating.patch
queue-3.10/mm-numa-ensure-anon_vma-is-locked-to-prevent-parallel-thp-splits.patch
queue-3.10/mm-numa-avoid-unnecessary-work-on-the-failure-path.patch
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