[PATCH] nfs: nfs_getattr() can't call nfs_sync_mapping_range() for non-regular files

Looks like we need a check in nfs_getattr() for a regular file. It makes
no sense to call nfs_sync_mapping_range() on anything else. I think that
should fix your problem: it will stop the NFS client from interfering
with dirty pages on that inode's mapping.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Olof Johansson <olof@lixom.net>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/nfs/inode.c

@@ -429,7 +429,8 @@ int nfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
 	int err;
 
 	/* Flush out writes to the server in order to update c/mtime */
-	nfs_sync_mapping_range(inode->i_mapping, 0, 0, FLUSH_NOCOMMIT);
+	if (S_ISREG(inode->i_mode))
+		nfs_sync_mapping_range(inode->i_mapping, 0, 0, FLUSH_NOCOMMIT);
 
 	/*
 	 * We may force a getattr if the user cares about atime.