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Date: Fri, 21 Sep 2007 21:46:39 +0100 (BST)
From: Hugh Dickins <hugh@veritas.com>
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To: Christoph Lameter <clameter@sgi.com>
cc: linux-kernel@vger.kernel.org
Subject: [PATCH 4/6] LBS: fix oops in try_to_release_page
In-Reply-To: <Pine.LNX.4.64.0709212141220.6532@blonde.wat.veritas.com>
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It's uncommon, but try_to_release_page is sometimes called when
page->mapping is NULL (see the check for mapping further down):
so its VM_BUG_ON(mapping_order(mapping)...) just causes an oops.
There seem to be enough of those checks already, and no special
reason to have one right here: just delete it.

Signed-off-by: Hugh Dickins <hugh@veritas.com>

--- 2.6.23-rc6-lbs/mm/filemap.c	2007-09-11 20:01:08.000000000 +0100
+++ linux/mm/filemap.c	2007-09-14 12:00:06.000000000 +0100
@@ -2247,7 +2247,6 @@ int try_to_release_page(struct page *pag
 	struct address_space * const mapping = page->mapping;
 
 	BUG_ON(!PageLocked(page));
-	VM_BUG_ON(mapping_order(mapping) != page_cache_page_order(page));
 	if (PageWriteback(page))
 		return 0;