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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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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.