+ mm-mempolicy-remove-bug_on-checks-for-vma-inside-mpol_misplaced.patch added to -mm tree

+ mm-mempolicy-remove-bug_on-checks-for-vma-inside-mpol_misplaced.patch added to -mm tree

[akpm]

The patch titled
     Subject: mm/mempolicy.c: remove BUG_ON() checks for VMA inside mpol_misplaced()
has been added to the -mm tree.  Its filename is
     mm-mempolicy-remove-bug_on-checks-for-vma-inside-mpol_misplaced.patch

This patch should soon appear at
    http://ozlabs.org/~akpm/mmots/broken-out/mm-mempolicy-remove-bug_on-checks-for-vma-inside-mpol_misplaced.patch
and later at
    http://ozlabs.org/~akpm/mmotm/broken-out/mm-mempolicy-remove-bug_on-checks-for-vma-inside-mpol_misplaced.patch

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------------------------------------------------------
From: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Subject: mm/mempolicy.c: remove BUG_ON() checks for VMA inside mpol_misplaced()

VMA and its address bounds checks are too late in this function.  They
must have been verified earlier in the page fault sequence.  Hence just
remove them.

Link: http://lkml.kernel.org/r/20170901130137.7617-1-khandual@linux.vnet.ibm.com
Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Suggested-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/mempolicy.c |    5 -----
 1 file changed, 5 deletions(-)

diff -puN mm/mempolicy.c~mm-mempolicy-remove-bug_on-checks-for-vma-inside-mpol_misplaced mm/mempolicy.c
--- a/mm/mempolicy.c~mm-mempolicy-remove-bug_on-checks-for-vma-inside-mpol_misplaced
+++ a/mm/mempolicy.c
@@ -2233,17 +2233,12 @@ int mpol_misplaced(struct page *page, st
 	int polnid = -1;
 	int ret = -1;
 
-	BUG_ON(!vma);
-
 	pol = get_vma_policy(vma, addr);
 	if (!(pol->flags & MPOL_F_MOF))
 		goto out;
 
 	switch (pol->mode) {
 	case MPOL_INTERLEAVE:
-		BUG_ON(addr >= vma->vm_end);
-		BUG_ON(addr < vma->vm_start);