Patch inspired by Andi Kleen. SGI-PV: 971186 SGI-Modid: xfs-linux-melb:xfs-kern:30000a Signed-off-by: David Chinner <dgc@sgi.com> Signed-off-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>