From: David Miller <davem@davemloft.net>
Date: Thu, 1 Mar 2007 04:13:13 +0000 (-0800)
Subject: [PATCH] Bug in MM_RB debugging
X-Git-Tag: v2.6.21-rc3~168
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=d1af65d13f3625543916a85c86d02826df910fcf;p=karo-tx-linux.git

[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>
---

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)) {