Messages in this thread | | | Subject | Re: [NFS] 2.6.17.8 - do_vfs_lock: VFS is out of sync with lock manager! | From | Trond Myklebust <> | Date | Mon, 21 Aug 2006 15:54:58 -0400 |
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On Mon, 2006-08-21 at 13:34 +1000, Neil Brown wrote: > Looking in fs/nfs/file.c (at 2.6.18-rc4-mm1 if it matters, but 2.6.17 > is much the same) > > - do_vfs_lock is only called when the filesystem was mounted with > -o nolock EXCEPT > - If a lock request to the server in interrupted (when mounted with > -o intr) then do_vfs_lock is called to try to get the lock > locally. Normally equivalent code will be called inside > fs/lockd/clntproc.c when the server replies that the lock has been > gained. In the case of an interrupt though this doesn't happen > but the lock may still have happened on the server. So we record > locally that the lock was gained, to ensure that it gets unlocked > when the process exits. > > As you don't have '-o nolocks' you must be hitting the second case. > The lock call to the server returns -EINTR or -ERESTARTSYS and > do_vfs_lock is called just-in-case. > As this is a just-in-case call, it is quite possible that the lock is > held by some other process, so getting an error is entirely possible. > So printing the message in this case seems wrong. > > On the other hand, printing the message in any other case seems wrong > too, as server locking is not being used, so there is nothing to get > out of sync with. > > As a further complication, I don't think that in the just-in-case > situation that it should risk waiting for the lock. > Now maybe we can be sure there is a pending signal which will break > out of any wait (though I'm worried about -ERESTARTSYS - that doesn't > imply a signal does it?), but I would feel more comfortable if > FL_SLEEP were turned off in that path. > > So: Trond: Any obvious errors in the above? > Is the following patch ok?
Could we instead replace it with a dprintk() that returns the value of "res"? That will keep it useful for debugging purposes.
Cheers, Trond
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