[PATCH] Bug in MM_RB debugging

The code is seemingly trying to make sure that rb_next() brings us to
successive increasing vma entries.

But the two variables, prev and pend, used to perform these checks, are
never advanced.

Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Andrea Arcangeli <andrea@novell.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/mm/mmap.c b/mm/mmap.c
index eb509ae76553..84f997da78d7 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -299,6 +299,8 @@ static int browse_rb(struct rb_root *root)
                         printk("vm_end %lx < vm_start %lx\n", vma->vm_end, vma->vm_start);
                 i++;
                 pn = nd;
+                prev = vma->vm_start;
+                pend = vma->vm_end;
         }
         j = 0;
         for (nd = pn; nd; nd = rb_prev(nd)) {