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 5718318D638; Mon, 26 Aug 2024 15:09:02 +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=1724684942; cv=none; b=P/y6G5JLJYQ13JV9OFLthHt3l7RvOq/x0TF39WZ4owf2JENcWsto1nwuQgIc7gfe4aIo0RS8wBXOp+tCDHV6am/DyZwXlll/K4YgPcWhSmb6v4/tL5gqa++4G5sJoHs+EoT4ib50feTWznypZYz6nXYkon4gyniXEPKYKcRpZyU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724684942; c=relaxed/simple; bh=1FcWwVmq5wSunT5cmUVeAwOQUJR8rsIt/3WQGn6zDpI=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=eDCebxRQufk+MMGxjPD+n9aUHP++OEc4R0DyLOrWyRuNdxwmwqaCMWwVZ746cqcypDoDot0tv+JP1D1ofoEncQqdNVcJJ9aCeNwqKqp5Er6VFQI+eO4+ueNzlifaXkP3ikiLZcLEWT4ybgMSpdLZRefg4L8frzYQlfU20/HRBOs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=k2NZI2pV; 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="k2NZI2pV" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7DCC5C4FF64; Mon, 26 Aug 2024 15:09:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1724684941; bh=1FcWwVmq5wSunT5cmUVeAwOQUJR8rsIt/3WQGn6zDpI=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=k2NZI2pVGyNE72plXR7hlNROMm3N2/0rTa26L/M4UkwzEbKd1IpFZ8Xj6MJh4tDL1 rXHS8BQxL2EifJ4qEcgnd4C5WQB90ouh3RvOyRfpyzcTnR258xIAZawTLVz6wWBfF3 RsdcUdEkpH0CsbRJXXRf7x9HvIroIx+T8afNouLAzfyqgY+xusbe6m10WPXdjVz8b0 /Yh7UOaj+umBjkgaNiO6CdmDZDUDggBJI9q42dnu3o1nrsDicrUxfToHf+k7zF8X09 0Net8ZIE5YkcRFU2Mp0WJsq+rpW8RAFQ53ird/XZyAv96D/85/NpEkpVyKpR5kw/d+ tl8ZIt5w+/Crg== Date: Mon, 26 Aug 2024 08:09:00 -0700 From: Jakub Kicinski To: Gal Pressman Cc: Eric Dumazet , Alexander Lobakin , "David S. Miller" , Paolo Abeni , David Ahern , Xuan Zhuo , Andrew Lunn , Willem de Bruijn , nex.sw.ncis.osdt.itp.upstreaming@intel.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH net-next v4 2/6] netdev_features: remove unused __UNUSED_NETIF_F_1 Message-ID: <20240826080900.57210004@kernel.org> In-Reply-To: References: <20240821150700.1760518-1-aleksander.lobakin@intel.com> <20240821150700.1760518-3-aleksander.lobakin@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=UTF-8 Content-Transfer-Encoding: quoted-printable On Sun, 25 Aug 2024 11:19:49 +0300 Gal Pressman wrote: > On 21/08/2024 18:43, Eric Dumazet wrote: > > On Wed, Aug 21, 2024 at 5:07=E2=80=AFPM Alexander Lobakin > > wrote: =20 > >> > >> NETIF_F_NO_CSUM was removed in 3.2-rc2 by commit 34324dc2bf27 > >> ("net: remove NETIF_F_NO_CSUM feature bit") and became > >> __UNUSED_NETIF_F_1. It's not used anywhere in the code. > >> Remove this bit waste. > >> > >> It wasn't needed to rename the flag instead of removing it as > >> netdev features are not uAPI/ABI. Ethtool passes their names > >> and values separately with no fixed positions and the userspace > >> Ethtool code doesn't have any hardcoded feature names/bits, so > >> that new Ethtool will work on older kernels and vice versa. =20 > >=20 > > This is only true for recent enough ethtool (>=3D 3.4) > >=20 > > You might refine the changelog to not claim this "was not needed". > >=20 > > Back in 2011 (and linux-2.6.39) , this was needed for sure. > >=20 > > I am not sure we have a documented requirement about ethtool versions. > > =20 >=20 > This is a nice history lesson, so before the features infrastructure the > feature bits were considered as "ABI"? >=20 > I couldn't find a point in time where they were actually defined in the > uapi files? Keep in mind that include/uapi was introduced around v3.7, before=20 that IIUC everything under include/linux that wasn't protected by ifdef __KERNEL__ was uAPI. So all of include/linux/netdev_features.h