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Message-Id: <20090825182613.898529620@bombadil.infradead.org>
Date: Tue, 25 Aug 2009 14:21:43 -0400
From: Christoph Hellwig <hch@infradead.org>
Subject: [PATCH 9/9] xfs: switch to NOFS allocation under i_lock in
	xfs_attr_rmtval_get
References: <20090825182134.299870049@bombadil.infradead.org>
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To: xfs@oss.sgi.com

xfs_attr_rmtval_get is always called with i_lock held, but i_lock is taken
in reclaim context so all allocations under it must avoid recursions into
the filesystem.  

Reported by the new reclaim context tracing in lockdep.


Index: linux-2.6/fs/xfs/xfs_attr.c
===================================================================
--- linux-2.6.orig/fs/xfs/xfs_attr.c	2009-07-18 22:34:08.947532301 +0200
+++ linux-2.6/fs/xfs/xfs_attr.c	2009-07-18 22:35:44.786660003 +0200
@@ -2010,7 +2010,9 @@ xfs_attr_rmtval_get(xfs_da_args_t *args)
 			dblkno = XFS_FSB_TO_DADDR(mp, map[i].br_startblock);
 			blkcnt = XFS_FSB_TO_BB(mp, map[i].br_blockcount);
 			error = xfs_read_buf(mp, mp->m_ddev_targp, dblkno,
-					     blkcnt, XFS_BUF_LOCK, &bp);
+					     blkcnt,
+					     XFS_BUF_LOCK | XBF_DONT_BLOCK,
+					     &bp);
 			if (error)
 				return(error);
 

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