From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 308BFC7EE24 for ; Mon, 5 Jun 2023 23:16:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233193AbjFEXQ4 (ORCPT ); Mon, 5 Jun 2023 19:16:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50632 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229681AbjFEXQx (ORCPT ); Mon, 5 Jun 2023 19:16:53 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1D1F7A6 for ; Mon, 5 Jun 2023 16:16:53 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id A60C962BA8 for ; Mon, 5 Jun 2023 23:16:52 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A7039C433D2; Mon, 5 Jun 2023 23:16:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1686007012; bh=N0okavvmW+hN+zvpU/6hPbUTjAPKTkWMzVLTCfODKj0=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=oxFFZGeRo8w3FyjbFp8iGddkfxEkSm6B7ROKwrdD+49820oQHrBDX8pULUmIFAJAW BnZ4XHz/+UUUv00BYv/XgrekfAscVRexvdC/jGjZ3AXdXdLqXsuGCdRJdqejPYNoUA +coVOUM0GUiTbFv0VbHcsO19NhI8HzXYCsYqTPN9/Wh/T0WeMv9WzauRRhAkrCPNB1 7G6g4pE0SLuxuV8IbhPGSYNq3D4BTYISTw/UXwYtLMQSoh//yzHOVmmNO2cxARKvOh goVUi+tfdy0EBW0gpXZaRLvKfD1Z4PBFlmuGMfFmu5Hn4Osxm4u6KhVyC+Z+3CXFvw qfVbV/VNAWFQA== Date: Mon, 5 Jun 2023 16:16:50 -0700 From: Jakub Kicinski To: Matthieu Baerts Cc: mptcp@lists.linux.dev, "David S. Miller" , Eric Dumazet , Paolo Abeni , David Ahern , Mat Martineau , Stephen Hemminger , Hideaki YOSHIFUJI , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH net-next] ipv6: lower "link become ready"'s level message Message-ID: <20230605161650.4a844f42@kernel.org> In-Reply-To: <20230601-net-next-skip_print_link_becomes_ready-v1-1-7ff2b88dc9b8@tessares.net> References: <20230601-net-next-skip_print_link_becomes_ready-v1-1-7ff2b88dc9b8@tessares.net> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 02 Jun 2023 11:36:07 +0200 Matthieu Baerts wrote: > This following message is printed in the console each time a network > device configured with an IPv6 addresses is ready to be used: > > ADDRCONF(NETDEV_CHANGE): : link becomes ready > > When netns are being extensively used -- e.g. by re-creating netns' with > veth to discuss with each others for testing purposes like mptcp_join.sh > selftest does -- it generates a lot of messages like that: more than 700 > when executing mptcp_join.sh with the latest version. > > It looks like this message is not that helpful after all: maybe it can > be used as a sign to know if there is something wrong, e.g. if a device > is being regularly reconfigured by accident? But even then, there are > better ways to monitor and diagnose such issues. > > When looking at commit 3c21edbd1137 ("[IPV6]: Defer IPv6 device > initialization until the link becomes ready.") which introduces this new > message, it seems it had been added to verify that the new feature was > working as expected. It could have then used a lower level than "info" > from the beginning but it was fine like that back then: 17 years ago. > > It seems then OK today to simply lower its level, similar to commit > 7c62b8dd5ca8 ("net/ipv6: lower the level of "link is not ready" messages") > and as suggested by Mat [1], Stephen and David [2]. > > Link: https://lore.kernel.org/mptcp/614e76ac-184e-c553-af72-084f792e60b0@kernel.org/T/ [1] > Link: https://lore.kernel.org/netdev/68035bad-b53e-91cb-0e4a-007f27d62b05@tessares.net/T/ [2] > Suggested-by: Mat Martineau > Suggested-by: Stephen Hemminger > Suggested-by: David Ahern > Signed-off-by: Matthieu Baerts This appears to have been applied as commit f69de8aa4752 ("ipv6: lower "link become ready"'s level message") in net-next, thank you!