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 D88337E for ; Wed, 15 Nov 2023 09:41:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="saLsWmP8" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8A3A4C433C8; Wed, 15 Nov 2023 09:41:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1700041286; bh=OAzWPsYo5D8WnJx6au21vBR29LjQjry6cVcjju6Rt80=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=saLsWmP8+gKE35hVSYjF8yDyGVuN8fH3oOl4tSkTCqk9kf3WNKEGUzKZjbo4DIPb8 aYM5knXBon4iLCwTu+jrcmuTylA52apRIpAPkUHWuz0R6KXuRaW8Xr/io96puieptn Zt/jXwOFwaRQvT8sHTPgt052gXY6zGe9HTgktxDN4CoTLffeu31RSKh4wEH+MYs70x Pa06evWSURkjLsmDmzTzH81nNch4kmDsuFTGbFHTXoZjsJRMgkKyL609KVR94X/Fsw 4ihczZPTM+IlUXLQb2C/f4xZcdg5EGVesmPaioyA91VHeu8Ul/OHvvzD88TVGz9oTf 6oqFtPbN54Fyw== Date: Wed, 15 Nov 2023 09:41:22 +0000 From: Simon Horman To: Johnathan Mantey Cc: netdev@vger.kernel.org, sam@mendozajonas.com, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH net v3] Revert ncsi: Propagate carrier gain/loss events to the NCSI controller Message-ID: <20231115094122.GL74656@kernel.org> References: <20231113163029.106912-1-johnathanx.mantey@intel.com> <20231114194616.GG74656@kernel.org> <87bkbwvzwn.fsf@intel.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: <87bkbwvzwn.fsf@intel.com> On Tue, Nov 14, 2023 at 12:20:52PM -0800, Johnathan Mantey wrote: > > Simon Horman writes: > > > On Mon, Nov 13, 2023 at 08:30:29AM -0800, Johnathan Mantey wrote: > > > This reverts commit 3780bb29311eccb7a1c9641032a112eed237f7e3. > > > > > > The cited commit introduced unwanted behavior. > > > > > > The intent for the commit was to be able to detect carrier loss/gain > > > for just the NIC connected to the BMC. The unwanted effect is a > > > carrier loss for auxiliary paths also causes the BMC to lose > > > carrier. The BMC never regains carrier despite the secondary NIC > > > regaining a link. > > > > > > This change, when merged, needs to be backported to stable kernels. > > > 5.4-stable, 5.10-stable, 5.15-stable, 6.1-stable, 6.5-stable > > > > > > Fixes: 3780bb29311e ("ncsi: Propagate carrier gain/loss events to > > > the NCSI controller") > > > CC: stable@vger.kernel.org > > > Signed-off-by: Johnathan Mantey > > > > Hi Jonathan, > > > > thanks for addressing my feedback on v2. > > > > So far as addressing a regression goes, this looks good to me. > > But I do wonder what can be done about the issue that > > the cited commit was intended to address: will this patch regress things > > on that front? > > Unfortunately the original issue will reoccur. I'm not sure which behavior > is worse. What's been present for the lifespan of the ncsi driver, or this > new issue I've introduced. In both instances a cable unplug causes > undesirable behavior. I'm going to investigate solving this for Intel's > specific use case ATM. NCSI has numerous modes in which it can be > configured. I don't have a good feel for how to generalize the code given > the side effect introduced by my change. Thanks Jonathan, I agree that is a bit of a conundrum without a working fix available. I would lean towards the old bug being somehow better than the new one - better the devil you know than the one you don't. So, FWIIW, from a pragmatic pov I'm happy with this patch. Reviewed-by: Simon Horman