This was submitted for 2.6.26-rc8-mm1 but it must have gotten overlooked:
diff --git a/mm/mmap.c b/mm/mmap.c

index 4c5211b..3d65a03 100644

--- a/mm/mmap.c

+++ b/mm/mmap.c

@@ -372,7 +372,7 @@ find_vma_prepare(struct mm_struct *mm, unsigned long addr,

 		if (vma_tmp->vm_end > addr) {

 			vma = vma_tmp;

 			if (vma_tmp->vm_start <= addr)

-				return vma;

+				break;

 			__rb_link = &__rb_parent->rb_left;

 		} else {

 			rb_prev = __rb_parent;

--

True, thanks, I guess that's my fault: it got stalled by me, because I

found it unsatisfying to fix the uninitialization from a compiler point

of view, whilst leaving it in an undefined state from a usability point

of view.  But since nothing does use those fields in this case, and my

amateurish treephobic experiments didn't find a quick solution to that,

I guess this is an improvement which should go in.
But please, let's credit Benny who posted it, and give his explanation

of what the patch is for, with some additional comment from me.  Which

leaves you out - "Reminded-by: Ryan Hope <rmh3093@gmail.com>"?
From: Benny Halevy <bhalevy@panasas.com>
gcc 4.3.0 correctly emits the following warnings.

When a vma covering addr is found, find_vma_prepare indeed returns without

setting pprev, rb_link, and rb_parent.
/usr0/export/dev/bhalevy/git/linux-pnfs-bh-nfs41/mm/mmap.c: In function =E2=

=80=98insert_vm_struct=E2=80=99:

/usr0/export/dev/bhalevy/git/linux-pnfs-bh-nfs41/mm/mmap.c:2085: warning: =

=E2=80=98rb_parent=E2=80=99 may be used uninitialized in this function

/usr0/export/dev/bhalevy/git/linux-pnfs-bh-nfs41/mm/mmap.c:2085: warning: =

=E2=80=98rb_link=E2=80=99 may be used uninitialized in this function

/usr0/export/dev/bhalevy/git/linux-pnfs-bh-nfs41/mm/mmap.c:2084: warning: =

=E2=80=98prev=E2=80=99 may be used uninitialized in this function

/usr0/export/dev/bhalevy/git/linux-pnfs-bh-nfs41/mm/mmap.c: In function =E2=

=80=98copy_vma=E2=80=99:

/usr0/export/dev/bhalevy/git/linux-pnfs-bh-nfs41/mm/mmap.c:2124: warning: =

=E2=80=98rb_parent=E2=80=99 may be used uninitialized in this function

/usr0/export/dev/bhalevy/git/linux-pnfs-bh-nfs41/mm/mmap.c:2124: warning: =

=E2=80=98rb_link=E2=80=99 may be used uninitialized in this function

/usr0/export/dev/bhalevy/git/linux-pnfs-bh-nfs41/mm/mmap.c:2123: warning: =

=E2=80=98prev=E2=80=99 may be used uninitialized in this function

/usr0/export/dev/bhalevy/git/linux-pnfs-bh-nfs41/mm/mmap.c: In function =E2=

=80=98do_brk=E2=80=9...
[ message continues ]

Yeah original author should get credit, i just didnt go back an look,

thanks for doing that.
--

I forgot to mention that this patch is for 2.6.27-rc1-mm1...
-Ryan
--