On Sun, 2009-12-13 at 16:39 -0500, J. Bruce Fields wrote: > On a recent kernel: > > # mount -tnfs4 pearlet1:/ /mnt/ > # find /mnt/ > /mnt/ > find: File system loop detected; `/mnt/DIR' is part of the same > file system loop as `/mnt/'. > > Here /mnt/DIR is a server-side mountpoint, hence has a different fsid > than /mnt/. Wireshark confirms that the server is returning a different > fsid. However, 'strace -v find /mnt/' shows stat returning > st_dev=makedev(0, 22) for both /mnt and /mnt/DIR. > > If I then do a 'ls /mnt/DIR', followed by another find, the error goes > away, and this time an strace shows that stat is returning (0, 23) for > /mnt/DIR. > > I don't see any obvious problem with the network trace, so it looks to > me like the client is failing to recognize the mountpoint when it > should? This is a known consequence of the way we treat submounts (and referrals); we're basically treating them as a special kind of symlink. The problem then arises when syscalls such as stat() fail to set the LOOKUP_FOLLOW flag, and so the user is granted a temporary peek of the underlying inode. I'm not sure how we should treat this. I suppose we could change the test in __link_path_walk() so that it always call follow_link() if the inode is not a symlink... Cheers Trond -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
