From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Lameter <clameter@sgi.com>
Date: Tue, 23 May 2006 17:43:49 +0000
Subject: [1/5] follow_page: do not put_page if FOLL_GET not specified.
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To: akpm@osdl.org
Cc: Hugh Dickins <hugh@veritas.com>, linux-ia64@vger.kernel.org, Peter Zijlstra <a.p.zijlstra@chello.nl>, Lee Schermerhorn <lee.schermerhorn@hp.com>, Nick Piggin <nickpiggin@yahoo.com.au>, linux-mm@kvack.org, Andi Kleen <ak@suse.de>, Christoph Lameter <clameter@sgi.com>, KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>

follow: no put_page() if FOLL_GET not specified.

Seems that one of the side effects of the dirty pages patch in
2.6.17-rc4-mm3 is that follow_pages does a page_put if FOLL_GET is
not set in the flags passed to it. This breaks sys_move_pages()
page status determination.

Only put_page if we did a get_page() before.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Index: linux-2.6.17-rc4-mm3/mm/memory.c
=================================--- linux-2.6.17-rc4-mm3.orig/mm/memory.c	2006-05-22 18:03:32.280767264 -0700
+++ linux-2.6.17-rc4-mm3/mm/memory.c	2006-05-23 10:01:48.917295988 -0700
@@ -964,7 +964,7 @@ struct page *follow_page(struct vm_area_
 			set_page_dirty(page);
 		mark_page_accessed(page);
 	}
-	if (!(flags & FOLL_GET))
+	if (!(flags & FOLL_GET) && (flags & FOLL_TOUCH))
 		put_page(page);
 	goto out;