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Date: Thu, 16 Nov 2023 16:06:50 +0100
From: Oleg Nesterov <oleg@redhat.com>
To: David Howells <dhowells@redhat.com>
Cc: Marc Dionne <marc.dionne@auristor.com>,
	"David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
	Al Viro <viro@zeniv.linux.org.uk>,
	Chuck Lever <chuck.lever@oracle.com>, linux-afs@lists.infradead.org,
	netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] rxrpc_find_service_conn_rcu: use read_seqbegin() rather
 than read_seqbegin_or_lock()
Message-ID: <20231116150650.GF18748@redhat.com>
References: <20231116141951.GE18748@redhat.com>
 <20231116131849.GA27763@redhat.com>
 <20231027095842.GA30868@redhat.com>
 <104932.1700142106@warthog.procyon.org.uk>
 <112162.1700146930@warthog.procyon.org.uk>
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X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.2

On 11/16, David Howells wrote:
>
> Oleg Nesterov <oleg@redhat.com> wrote:
>
> > > > 	- the usage of read_seqbegin_or_lock/need_seqretry in
> > > > 	  this code makes no sense because read_seqlock_excl()
> > > > 	  is not possible
> > >
> > > Not exactly.  I think it should take a lock on the second pass.
> >
> > OK, then how about the patch below?
>
> That seems to work.

OK, I'll send V2 tomorrow.

Should I change fs/afs the same way?

Oleg.