linux-kernel - Re: [PATCH] NFS: Retry the CLOSE if the embedded GETATTR is rejected with ERR

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Message-ID: <a0babbb7d58f02769a6ce40d029768e7221acf24.camel@hammerspace.com>
Date:   Wed, 18 Nov 2020 03:17:20 +0000
From:   Trond Myklebust <trondmy@...merspace.com>
To:     "anchalag@...zon.com" <anchalag@...zon.com>,
        "linux-nfs@...r.kernel.org" <linux-nfs@...r.kernel.org>,
        "anna.schumaker@...app.com" <anna.schumaker@...app.com>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] NFS: Retry the CLOSE if the embedded GETATTR is rejected
 with ERR_STALE

On Wed, 2020-11-18 at 00:24 +0000, Anchal Agarwal wrote:
> If our CLOSE RPC call is rejected with an ERR_STALE error, then we
> should remove the GETATTR call from the compound RPC and retry.
> This could happen in a scenario where two clients tries to access
> the same file. One client opens the file and the other client removes
> the file while it's opened by first client. When the first client
> attempts to close the file the server returns ESTALE and the file
> ends
> up being leaked on the server. This depends on how nfs server is
> configured and is not reproducible if running against nfsd.

That would be a seriously broken server. If you return NFS4ERR_STALE to
the client, you cannot expect any further interaction with that file
from the client. It won't try to send CLOSE or DELEGRETURN or any other
stateful operation.

-- 
Trond Myklebust
Linux NFS client maintainer, Hammerspace
trond.myklebust@...merspace.com