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 7E9563D75C3; Mon, 13 Apr 2026 14:11:31 +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=1776089491; cv=none; b=u0GK8DKUy0Zh0oD6dEUDsF/TMPK1MlIDaTsfmzN/lFoY6nr6+d/HhNhanpfoSVMLzxIRe+cA4Ze8plj/ovsEyCuGzZ63YIYya12bBnVbf8kn7N07bvqjcxmCqKeUeIjm2NurxBajG/yK3JE8dwJpzsXVIEKrCQH5EJdbEzRlixk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776089491; c=relaxed/simple; bh=gFRvrKXlOfg+aEGi39wpVj9CoHvkfV4SW9XjwhO71Bg=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=NT9nx60rWuWtxgpXpgamRXf0KlMHUAU03D2goTzO+2aVFatTlN0NpSt9bDQk7kaaXhtSJNAlgqHcqcTE7zS/sqCY70DDgJFJC4iF+9E0Pvkqwa8U5WAUOUflkjHnhMN29t/v4YfQzqxxc+v/j7bRWMBbYtxcpQv8KaQSrXzQnSQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Vuz8JIgy; 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="Vuz8JIgy" Received: by smtp.kernel.org (Postfix) with ESMTPSA id AD6D9C2BCAF; Mon, 13 Apr 2026 14:11:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1776089491; bh=gFRvrKXlOfg+aEGi39wpVj9CoHvkfV4SW9XjwhO71Bg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Vuz8JIgyGFQs79J7jNYhLXjVTEJKcIy7q5fIMQvp69Rs6UAmh9zywB6sRRJyuSPZ2 g+pdHQ203cM48BifuF+R1XKrQAour1unMgz1Hs9HNTMCQzb2M3F4CRrv4S2bN2AAfT 29qhXHvawfyEttE99sA2TD0YgSFFuxY+c2+oUt2NwsZH5HNRQi85n8aohpaOvSd32v fM9Vygo51KBRkcEEhB8B9OMaZ7kqOmtJ3ZeRTprb2EqP88EMVtZe1TDG9WyHnoQiru RKdLCkyaoXwYB6kV24hu8LH8p1H1q0ApAoO5ee8ZbPe7R36iMv9CJbvNo5XyKF14mn aGz59T8PyA/0w== Date: Mon, 13 Apr 2026 15:11:26 +0100 From: Simon Horman To: Matt Fleming Cc: Tony Nguyen , Przemek Kitszel , Andrew Lunn , "David S . Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , intel-wired-lan@lists.osuosl.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@cloudflare.com, Matt Fleming Subject: Re: [PATCH net] ice: Fix missing 1's complement negation in GCS raw checksum Message-ID: <20260413141126.GR469338@kernel.org> References: <20260408190214.1287708-1-matt@readmodwrite.com> Precedence: bulk X-Mailing-List: linux-kernel@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: <20260408190214.1287708-1-matt@readmodwrite.com> On Wed, Apr 08, 2026 at 08:02:14PM +0100, Matt Fleming wrote: > From: Matt Fleming > > Commit 905d1a220e8d ("ice: Add E830 checksum offload support") added > Generic Checksum (GCS) support for E830 NICs but omitted the 1's > complement negation (~) when converting the hardware raw_csum to > skb->csum for CHECKSUM_COMPLETE. > > Without the negation, every CHECKSUM_COMPLETE packet fails the > fast-path validation in nf_ip_checksum() and falls through to software > checksumming via __skb_checksum_complete(), which triggers the > rate-limited "hw csum failure" warning. Packets are still accepted > (the software recheck passes) but hardware checksum offload is > effectively disabled and the warning floods dmesg on systems running > nf_conntrack on VLAN sub-interfaces. > > Multiple other drivers (idpf, ehea, iwlwifi, cassini, sunhme, enetc) > also apply ~ for CHECKSUM_COMPLETE. The ice driver was the only in-tree > user of csum_unfold() for CHECKSUM_COMPLETE that omitted it. > > Fixes: 905d1a220e8d ("ice: Add E830 checksum offload support") > Signed-off-by: Matt Fleming Reviewed-by: Simon Horman