-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Adam Litke <[EMAIL PROTECTED]>

Here's another breakage as a result of shared memory stacked files :(

The NUMA policy for a VMA is determined by checking the following (in the
order given):

1) vma->vm_ops->get_policy() (if defined)
2) vma->vm_policy (if defined)
3) task->mempolicy (if defined)
4) Fall back to default_policy

By switching to stacked files for shared memory, get_policy() is now always
set to shm_get_policy which is a wrapper function.  This causes us to stop
at step 1, which yields NULL for hugetlb instead of task->mempolicy which
was the previous (and correct) result.

This patch modifies the shm_get_policy() wrapper to maintain steps 1-3 for
the wrapped vm_ops.

(akpm: the refcounting of mempolicies is busted and this patch does nothing to
improve it)

Signed-off-by: Adam Litke <[EMAIL PROTECTED]>
Acked-by: William Irwin <[EMAIL PROTECTED]>
Cc: dean gaudet <[EMAIL PROTECTED]>
Cc: Christoph Lameter <[EMAIL PROTECTED]>
Cc: Andi Kleen <[EMAIL PROTECTED]>
Signed-off-by: Andrew Morton <[EMAIL PROTECTED]>
Signed-off-by: Chris Wright <[EMAIL PROTECTED]>
Signed-off-by: Greg Kroah-Hartman <[EMAIL PROTECTED]>
---

 ipc/shm.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- linux-2.6.21.6.orig/ipc/shm.c
+++ linux-2.6.21.6/ipc/shm.c
@@ -254,8 +254,10 @@ struct mempolicy *shm_get_policy(struct 
 
        if (sfd->vm_ops->get_policy)
                pol = sfd->vm_ops->get_policy(vma, addr);
-       else
+       else if (vma->vm_policy)
                pol = vma->vm_policy;
+       else
+               pol = current->mempolicy;
        return pol;
 }
 #endif

-- 
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