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	Mon, 19 Oct 2026 14:05:19 +0000
Date: Mon, 19 Oct 2026 15:05:19 +0100
From: Al Viro <viro@zeniv.linux.org.uk>
To: Avi Weiss <thnkslprpt@gmail.com>
Cc: Trond Myklebust <trondmy@kernel.org>, Anna Schumaker <anna@kernel.org>,
	Chuck Lever <cel@kernel.org>, Jeff Layton <jlayton@kernel.org>,
	NeilBrown <neil@brown.name>,
	Olga Kornievskaia <okorniev@redhat.com>,
	Dai Ngo <Dai.Ngo@oracle.com>, Tom Talpey <tom@talpey.com>,
	linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] sunrpc: instantiate rpc_pipefs dentry before publishing
 it
Message-ID: <20261019140519.GJ989762@ZenIV>
References: <20261019101117.54038-1-thnkslprpt@gmail.com>
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Sender: Al Viro <viro@ftp.linux.org.uk>

On Mon, Oct 19, 2026 at 01:11:17PM +0300, Avi Weiss wrote:
> rpc_mkpipe_dentry() publishes pipe->dentry before
> d_make_persistent() attaches its inode. A concurrent
> rpc_queue_upcall() or rpc_timeout_upcall_queue() can
> conceivably dereference the dentry while d_inode() is NULL.

Details, please...  I have no objections against the reordering
per se, but I would like to understand the scenario leading to
such a concurrent call.