Date: Thu, 2 Aug 2012 19:29:14 -0700 (PDT)
From: Andrei Warkentin <awarkentin@vmware.com>
To: linux-nfs@vger.kernel.org
Cc: Ed Goggin <egoggin@vmware.com>
Message-ID: <1592211005.4733808.1343960954717.JavaMail.root@vmware.com>
In-Reply-To: <1781697815.4540720.1343959078882.JavaMail.root@vmware.com>
Subject: Re: stale or not stale
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Sender: linux-nfs-owner@vger.kernel.org

----- Original Message -----
> From: "Ed Goggin" <egoggin@vmware.com>
> To: linux-nfs@vger.kernel.org
> Sent: Thursday, August 2, 2012 9:57:58 PM
> Subject: stale or not stale
> 
> 
> It seems that nfsd can return reply attributes with a link count of
> zero but without an NFS3ERR_STALE status.  We've seen this actually
> happen for a write request to a file with a single link that  is
> concurrently being removed without NLM lock protection.  What is the
> proper behavior here?

I think it would be worthwhile to add here that the the remove was not concurrent with the write, and at the time of the NFS write a new file with the same name existed, yet fh decoding picked up the old inode instead of reporting -ESTALE. FS was ext4.

In fact seen two things happen - n_link = 0 and n_link = 1, and in both cases we knew the file was unlink()ed and re-creat()ed.

A