From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from pandora.armlinux.org.uk (pandora.armlinux.org.uk [78.32.30.218]) (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 DCF99208B8; Mon, 26 Feb 2024 11:48:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=78.32.30.218 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708948093; cv=none; b=jN9L0K7q2aYnUhQzxLpizwfkCmi3uBEAJx4oEPYeJOU/Jq+Qdr26Ze9TJAI8T1UCWX59g2S4+PyS7y5RHFMLpq3rElOfkuvjvCaHvZD8gxtOXf7reMsmZXbRs7Kq+jTwai/YP3q4BVTz7qiRpBrkqYw/Z5KbRMoNqFD36CRgIU8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708948093; c=relaxed/simple; bh=kFr3B/ULY+gMSkUP5N9M2ZZcd1AQsK+54aUGpEWndtI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=J0DF4TDdijSanv8RUV8VEmMUHP69jvxdwiANPSffQhnYPZiL7JFuoCqpxlQIOkwKvX6Eh7qt6RRFXHB2xsUsGP/I5d7moJiJGvOTat4r+nQ5+TcUfw900WXd2usuds3XRjZoSN1t9UfdK0W/VoiEVgMrlzVed2n1+dUlzQhF7pY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=armlinux.org.uk; spf=none smtp.mailfrom=armlinux.org.uk; dkim=pass (2048-bit key) header.d=armlinux.org.uk header.i=@armlinux.org.uk header.b=brVvD7gL; arc=none smtp.client-ip=78.32.30.218 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=armlinux.org.uk Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=armlinux.org.uk Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=armlinux.org.uk header.i=@armlinux.org.uk header.b="brVvD7gL" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Sender:In-Reply-To: Content-Transfer-Encoding:Content-Type:MIME-Version:References:Message-ID: Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=Gw1YcQC9qtJ4/pe66V7YRq+GAf4l9U7OKSN0ldpLYSY=; b=brVvD7gLhZJfWAo8PU5vLdHgiY kdXs2ki0PBjRk/pm7+3gkSDljK1QxtoBZeyd8T+RUXMw9AUUjEuYYJ+vLcSnbqtqk74jX6Xc4GE3x XFX1+7DuIl4b7pTlP9DUxZvqxsMdrQ6/aAo5Yt5IyYF5DP+s36IinJu0HbOsg07TqnyCxHHgwX2Ky HnGs5GLG8BPOhvHM94GvuLxrxxNGy3WuXv4ekVOpOZC/OrkT3kvOMssX3fh+QLX6ieE1pn1MQDhnL JOis2meDoCyogwRu1Se4ystHBJPtbfLHPaoNB72w9rN9zygg7PMxSGBtjvAT3xrFex7WMTbppgRgj yjfwBftQ==; Received: from shell.armlinux.org.uk ([fd8f:7570:feb6:1:5054:ff:fe00:4ec]:56924) by pandora.armlinux.org.uk with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1reZSY-0003A6-2J; Mon, 26 Feb 2024 11:47:50 +0000 Received: from linux by shell.armlinux.org.uk with local (Exim 4.94.2) (envelope-from ) id 1reZSS-0006P5-Tm; Mon, 26 Feb 2024 11:47:44 +0000 Date: Mon, 26 Feb 2024 11:47:44 +0000 From: "Russell King (Oracle)" To: Christophe Leroy Cc: Charlie Jenkins , Guenter Roeck , David Laight , Palmer Dabbelt , Andrew Morton , Helge Deller , "James E.J. Bottomley" , Parisc List , Arnd Bergmann , "linux-kernel@vger.kernel.org" , Palmer Dabbelt , Linux ARM Subject: Re: [PATCH v10] lib: checksum: Use aligned accesses for ip_fast_csum and csum_ipv6_magic tests Message-ID: References: <20240223-fix_sparse_errors_checksum_tests-v10-1-b6a45914b7d8@rivosinc.com> <7ae930a7-3b10-4470-94ee-89cb650b3349@csgroup.eu> 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=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <7ae930a7-3b10-4470-94ee-89cb650b3349@csgroup.eu> Sender: Russell King (Oracle) On Mon, Feb 26, 2024 at 11:34:51AM +0000, Christophe Leroy wrote: > Le 23/02/2024 à 23:11, Charlie Jenkins a écrit : > > The test cases for ip_fast_csum and csum_ipv6_magic were not properly > > aligning the IP header, which were causing failures on architectures > > that do not support misaligned accesses like some ARM platforms. To > > solve this, align the data along (14 + NET_IP_ALIGN) bytes which is the > > standard alignment of an IP header and must be supported by the > > architecture. > > I'm still wondering what we are really trying to fix here. > > All other tests are explicitely testing that it works with any alignment. > > Shouldn't ip_fast_csum() and csum_ipv6_magic() work for any alignment as > well ? I would expect it, I see no comment in arm code which explicits > that assumption around those functions. No, these functions are explicitly *not* designed to be used with any alignment. They are for 16-bit alignment only. I'm not sure where the idea that "any alignment" has come from, but it's never been the case AFAIK that we've supported that - or if we do now, that's something which has crept in under the radar. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!