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Date:   Wed, 13 May 2020 19:29:37 -0400
From:   "J. Bruce Fields" <bfields@redhat.com>
To:     "J. Bruce Fields" <bfields@fieldses.org>
Cc:     Trond Myklebust <trondmy@hammerspace.com>,
        Anna Schumaker <schumakeranna@gmail.com>,
        linux-nfs@vger.kernel.org
Subject: Re: [PATCH] SUNRPC: 'Directory with parent 'rpc_clnt' already
 present!'
Message-ID: <20200513232937.GB34451@pick.fieldses.org>
References: <1589409520-1344-1-git-send-email-bfields@redhat.com>
 <20200513224033.GA1415@fieldses.org>
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On Wed, May 13, 2020 at 06:40:33PM -0400, J. Bruce Fields wrote:
> On Wed, May 13, 2020 at 06:38:40PM -0400, J. Bruce Fields wrote:
> > From: "J. Bruce Fields" <bfields@redhat.com>
> > 
> > Each rpc_client has a cl_clid which is allocated from a global ida, and
> > a debugfs directory which is named after cl_clid.
> > 
> > We're releasing the cl_clid before we free the debugfs directory named
> > after it.  As soon as the cl_clid is released, that value is available
> > for another newly created client.
> > 
> > That leaves a window where another client may attempt to create a new
> > debugfs directory with the same name as the not-yet-deleted debugfs
> > directory from the dying client.  Symptoms are log messages like
> > 
> > 	Directory 4 with parent 'rpc_clnt' already present!
> 
> This also cleared up a "file-max limit 199277 reached" warning, which
> suggests to me a leak in an error path somewhere (I think everything's
> supposed to work normally even if debugfs file createion fails), but I
> don't see it.

Whoops, I spoke to soon, I'm still seeing that warning, so that's an
unrelated issue.

--b.