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 X-Spam-Level: X-Spam-Status: No, score=-2.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A6EFEC54FD0 for ; Tue, 21 Apr 2020 16:55:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 79074206F4 for ; Tue, 21 Apr 2020 16:55:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=armlinux.org.uk header.i=@armlinux.org.uk header.b="PudUaazE" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729380AbgDUQze (ORCPT ); Tue, 21 Apr 2020 12:55:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43014 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1729038AbgDUQzc (ORCPT ); Tue, 21 Apr 2020 12:55:32 -0400 Received: from pandora.armlinux.org.uk (pandora.armlinux.org.uk [IPv6:2001:4d48:ad52:3201:214:fdff:fe10:1be6]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A0511C061A41 for ; Tue, 21 Apr 2020 09:55:31 -0700 (PDT) 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-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding: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=WjhgbaEbBW3u8OJNr5mxiJDIQfOQFRnAGsSZAkxI4Ck=; b=PudUaazEa9YkVoMl8hUmwa+W8 eqSVBuyamU1qlNTP5YiSmxvNv1W2N/KygVbgmFZfSaFy8Rhc4fxLVEHReDHAcs2Tg3xJ55V93G+pT exKQePYAqn7kKK7DwtH20u25uB3sVQHjJK3FtsadgWf9olHRerEkc6U4NeiJp4jUoAZkFm7ZqlkTA Vq0gIeaiLa/Ef4fdpXcY4uepUYDEiIRPx4S7Yr2/krsQARzRnRmazYQMwgFfUsfnCHlPsHQUqhul1 UVSofi/+2ykyGifMM9yRez2ZWtPZAyZs19LR9x99Qno3v2rPS/2FHXRrAW3fd5b+g+xAkhZ0buphx BWrbSmvwg==; Received: from shell.armlinux.org.uk ([fd8f:7570:feb6:1:5054:ff:fe00:4ec]:53318) by pandora.armlinux.org.uk with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jQwB7-0002oI-JN; Tue, 21 Apr 2020 17:55:21 +0100 Received: from linux by shell.armlinux.org.uk with local (Exim 4.92) (envelope-from ) id 1jQwB2-0007Ba-96; Tue, 21 Apr 2020 17:55:16 +0100 Date: Tue, 21 Apr 2020 17:55:16 +0100 From: Russell King - ARM Linux admin To: James Morse Cc: Jonathan Cameron , info@metux.net, catalin.marinas@arm.com, linux-kernel@vger.kernel.org, linuxarm@huawei.com, allison@lohutok.net, gregkh@linuxfoundation.org, Tian Tao , tglx@linutronix.de, Will Deacon , linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH] arm32: fix flushcache syscall with device address Message-ID: <20200421165515.GF25745@shell.armlinux.org.uk> References: <1587456514-61156-1-git-send-email-tiantao6@hisilicon.com> <20200421081239.GA15439@willie-the-truck> <20200421121651.000009f0@Huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 21, 2020 at 05:50:22PM +0100, James Morse wrote: > Hi guys, > > (Subject Nit: arm64, as that is what your patch modifies) That is irrelevent. This is a compatibility interface which is supposed to reflect the arm32 implementation. Augmenting a compatibility interface to do more than what it's counterpart that it's supposed to be compatible with is senseless. The API concerned is an ARM32 API which is expected to only be used for ensuring I/D cache coherency, it is not for DMA. Augmenting it on ARM64 for DMA is senseless. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line in suburbia: sync at 10.2Mbps down 587kbps up