From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 280B51E48A for ; Sun, 5 May 2024 14:53:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714920818; cv=none; b=hUI8pY5yBvqO/bLSsb6MtVLmVLMzvBdLutKi8SEdIJjfrVQpFz5hFogw1vITd6RWNS79MmwXRXWKViIRuK94gqZPG9d/xB9xAxNhDMyeKDR4lb+dOsIf43bEa7j6yADRcRKf46I2tbQj0U5OFFDvE1bCbS+8QbhUjxfTVWjiZpw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714920818; c=relaxed/simple; bh=U3p7X9MpCsLkBtiN+hiDQozS0v4BnNcA5vikdd4YLnY=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=e0W5k/fx1jMlbk2y6WKcszrZSC8B4YettWxEn4iS1gh7r62D5AknNd+eET9GpCWcUiX5C5XzWuV8bjd4JBh9HQKys6hd165ls9JODfuh8cmwkqFFUEXCHVtdrn41XNPwY+Eh0YcqyjwTsRfRS3k9yhGGqxh0WIa8HGfEAuQd/ck= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=btUGtZZ/; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="btUGtZZ/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 44FAFC113CC; Sun, 5 May 2024 14:53:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1714920817; bh=U3p7X9MpCsLkBtiN+hiDQozS0v4BnNcA5vikdd4YLnY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=btUGtZZ/FvMMynkQCRKb6r+T8SaDtfuKz98k+2HGLNOa5jOoUPwIt+KucdGZwVuqe cFG4PqbXFOD7crk6GHAL+6gxfEoEqqXONrsnd5DWIdxzBen9SA3kJY+K17Hp5NnRUU GmHd/SyoiJ8C7bNALZX8PBOfYt2MpKOGfInL2MT8EDzfszLLowyFvySJRrbMpNTXU7 60GEHrSFt5RTwn0/g+ySL0vmi7OX3dsyn92CmRTeoyEAfKczZkdQkfGyfMhxvpxQSU CEtV2gFNzeOiLW/+Yf9cpW4aavUIpbDJK/ojNI04Yxoi42I+vdMuukGKXrGFkTZdPK ZitdxdR5xc8zQ== Date: Sun, 5 May 2024 15:52:03 +0100 From: Simon Horman To: Eric Dumazet Cc: "David S . Miller" , Jakub Kicinski , Paolo Abeni , netdev@vger.kernel.org, eric.dumazet@gmail.com Subject: Re: [PATCH net-next 6/8] rtnetlink: do not depend on RTNL in rtnl_fill_proto_down() Message-ID: <20240505145203.GE67882@kernel.org> References: <20240503192059.3884225-1-edumazet@google.com> <20240503192059.3884225-7-edumazet@google.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240503192059.3884225-7-edumazet@google.com> On Fri, May 03, 2024 at 07:20:57PM +0000, Eric Dumazet wrote: > Change dev_change_proto_down() and dev_change_proto_down_reason() > to write once on dev->proto_down and dev->proto_down_reason. > > Then rtnl_fill_proto_down() can use READ_ONCE() annotations > and run locklessly. > > rtnl_proto_down_size() should assume worst case, > because readng dev->proto_down_reason multiple > times would be racy without RTNL in the future. > > Signed-off-by: Eric Dumazet Reviewed-by: Simon Horman