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=-6.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED 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 33378C433DB for ; Fri, 8 Jan 2021 20:23:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E89A023AC4 for ; Fri, 8 Jan 2021 20:23:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729299AbhAHUXR (ORCPT ); Fri, 8 Jan 2021 15:23:17 -0500 Received: from mail.kernel.org ([198.145.29.99]:46330 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729017AbhAHUXQ (ORCPT ); Fri, 8 Jan 2021 15:23:16 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id A3FC723AC2; Fri, 8 Jan 2021 20:22:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1610137355; bh=eaVy/h1sqS72eojXpxZdrAkyp/2+sHG6P9GrVWKTzf0=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=jDtcPFPT0sAh3JVCRwf39s1NaB8Sw80GSm3jJCWgg+Qiv8paW/ZpBb2arPhI2wrA2 Z7aRP6OfCwaFuRJp0PxaG9pa8+mJt+zeJJlFZaTUU3vAursh8I1Bo7skbLBgQ3tdqs ubvSITIFfNJLZzEYTr7scbKMKnmtD9qJ9bM7udSotn/pIo2isSJH2kuQAWhTxgomVw 3e5ZUeU7XzoTk/C7GXeQl5Z1Xtg6F33Qy9o+PktmY1po4X11WzEfHrjdYcwQaID5Ch Qpcwtq1RtGGb/NlZ2W4z7IHqbsuCBRUemTSMHvRvBBwYnWg37kxKsSmBJGa3w/n4lQ TTIIW5OFOuNtg== Received: by mail-oi1-f170.google.com with SMTP id p5so12732154oif.7; Fri, 08 Jan 2021 12:22:35 -0800 (PST) X-Gm-Message-State: AOAM5309mQGJFCtHtMvOihiPQfANNluwAi3kPo16x9Ddsinz8PDxo/iv OzD/jhdipklGv7j1hVFdfRr87ZCAAOOCG4QgDyo= X-Google-Smtp-Source: ABdhPJwVTMd3FygXgJ3u5lYNHsXmgTpMPMS6Ohlq8w/Sp951W2jKYng2WW7Hs1gngp0AbUAXySzAfu0RQUSAdgliM64= X-Received: by 2002:aca:e103:: with SMTP id y3mr3288783oig.11.1610137355049; Fri, 08 Jan 2021 12:22:35 -0800 (PST) MIME-Version: 1.0 References: <20210106115359.GB26994@C02TD0UTHF1T.local> <20210106135253.GJ1551@shell.armlinux.org.uk> <20210106172033.GA2165@willie-the-truck> <20210106223223.GM1551@shell.armlinux.org.uk> <20210107111841.GN1551@shell.armlinux.org.uk> <20210107124506.GO1551@shell.armlinux.org.uk> <20210107133747.GP1551@shell.armlinux.org.uk> <20210108092655.GA4031@willie-the-truck> In-Reply-To: From: Arnd Bergmann Date: Fri, 8 Jan 2021 21:22:18 +0100 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: Aarch64 EXT4FS inode checksum failures - seems to be weak memory ordering issues To: Linus Torvalds Cc: Will Deacon , Peter Zijlstra , Russell King - ARM Linux admin , linux-toolchains@vger.kernel.org, Mark Rutland , "Theodore Ts'o" , "linux-kernel@vger.kernel.org" , Andreas Dilger , Ext4 Developers List , Linux ARM Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jan 8, 2021 at 9:02 PM Linus Torvalds wrote: > On Fri, Jan 8, 2021 at 1:27 AM Will Deacon wrote: > > > > On Fri, Jan 08, 2021 at 10:21:54AM +0100, Peter Zijlstra wrote: > > > On Thu, Jan 07, 2021 at 10:20:38PM +0100, Arnd Bergmann wrote: > > > > On Thu, Jan 7, 2021 at 2:37 PM Russell King - ARM Linux admin > > I appreciate Arnd pointing out "--std=gnu11", though. What are the > actual relevant language improvements? > > Variable declarations in for-loops is the only one I can think of. I > think that would clean up some code (and some macros), but might not > be compelling on its own. I think that was the main one, as most of --std=c11 is already part of --std=gnu89 as a gnu extension. There were a few things that came up with clang porting, as clang is somewhat closer to gnu11 than to gnu89, but I don't remember exactly what that was. I would still like to improve READ_ONCE()/get_user()/cmpxchg() further using __auto_type and _Generic where possible, but I think that was already supported in gcc-4.9, and does not require gcc-5. Arnd 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=-4.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 55E93C433DB for ; Fri, 8 Jan 2021 20:24:10 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0A2F723AC0 for ; Fri, 8 Jan 2021 20:24:10 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0A2F723AC0 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:To:Subject:Message-ID:Date:From:In-Reply-To: References:MIME-Version:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=pxp0egDG1K6XHpL5SmQC6OLqENmtm1rV3x2eoBHWvDw=; b=d2wXmRqh5uKmbh87uu+9AKTQj nKNQUilxiZsLa1CEDepNCkCe/DwOvPz/0a6p7m/9IJpUHI01kMbn/TcETJJJiF3B/68kSF+jPyiUB 8UMplnVifIcsoT9Q1HxlIHVLWaQmuVYhw/AMpKBlbpNf0R4DL7tSmhSbj9gAOUq+qlKld/294PIEU uJ/khsO7U5npAn5DVX13hTWj14meZB0J5ixkyaWF4sS4AMKcrn8fWxxsfc8QozQ+SjRpUntfbPbnS ngp5Jdc2mtlp87dsKRqxykCwSTirSDBl3EVJpeVwVQJ9JKwayrlWYUHEPEnGDlRZGLXcXoUQhQXrA uRQiZFmMg==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kxyHP-0003M0-Bi; Fri, 08 Jan 2021 20:22:39 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kxyHM-0003Ka-Rs for linux-arm-kernel@lists.infradead.org; Fri, 08 Jan 2021 20:22:37 +0000 Received: by mail.kernel.org (Postfix) with ESMTPSA id AC2DD23AC9 for ; Fri, 8 Jan 2021 20:22:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1610137355; bh=eaVy/h1sqS72eojXpxZdrAkyp/2+sHG6P9GrVWKTzf0=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=jDtcPFPT0sAh3JVCRwf39s1NaB8Sw80GSm3jJCWgg+Qiv8paW/ZpBb2arPhI2wrA2 Z7aRP6OfCwaFuRJp0PxaG9pa8+mJt+zeJJlFZaTUU3vAursh8I1Bo7skbLBgQ3tdqs ubvSITIFfNJLZzEYTr7scbKMKnmtD9qJ9bM7udSotn/pIo2isSJH2kuQAWhTxgomVw 3e5ZUeU7XzoTk/C7GXeQl5Z1Xtg6F33Qy9o+PktmY1po4X11WzEfHrjdYcwQaID5Ch Qpcwtq1RtGGb/NlZ2W4z7IHqbsuCBRUemTSMHvRvBBwYnWg37kxKsSmBJGa3w/n4lQ TTIIW5OFOuNtg== Received: by mail-oi1-f170.google.com with SMTP id d203so12800453oia.0 for ; Fri, 08 Jan 2021 12:22:35 -0800 (PST) X-Gm-Message-State: AOAM531h8F681s6PYmKrt2JxwA9QX6x3nQ5Y9+L2cqCQxKYTvpVmcY00 fvB8MYjTXG/M0TJsGCmycds482eGpHKkcRuyEcg= X-Google-Smtp-Source: ABdhPJwVTMd3FygXgJ3u5lYNHsXmgTpMPMS6Ohlq8w/Sp951W2jKYng2WW7Hs1gngp0AbUAXySzAfu0RQUSAdgliM64= X-Received: by 2002:aca:e103:: with SMTP id y3mr3288783oig.11.1610137355049; Fri, 08 Jan 2021 12:22:35 -0800 (PST) MIME-Version: 1.0 References: <20210106115359.GB26994@C02TD0UTHF1T.local> <20210106135253.GJ1551@shell.armlinux.org.uk> <20210106172033.GA2165@willie-the-truck> <20210106223223.GM1551@shell.armlinux.org.uk> <20210107111841.GN1551@shell.armlinux.org.uk> <20210107124506.GO1551@shell.armlinux.org.uk> <20210107133747.GP1551@shell.armlinux.org.uk> <20210108092655.GA4031@willie-the-truck> In-Reply-To: From: Arnd Bergmann Date: Fri, 8 Jan 2021 21:22:18 +0100 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: Aarch64 EXT4FS inode checksum failures - seems to be weak memory ordering issues To: Linus Torvalds X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210108_152237_009006_28013570 X-CRM114-Status: GOOD ( 16.81 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Theodore Ts'o , Peter Zijlstra , Russell King - ARM Linux admin , "linux-kernel@vger.kernel.org" , Andreas Dilger , linux-toolchains@vger.kernel.org, Ext4 Developers List , Will Deacon , Linux ARM Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Jan 8, 2021 at 9:02 PM Linus Torvalds wrote: > On Fri, Jan 8, 2021 at 1:27 AM Will Deacon wrote: > > > > On Fri, Jan 08, 2021 at 10:21:54AM +0100, Peter Zijlstra wrote: > > > On Thu, Jan 07, 2021 at 10:20:38PM +0100, Arnd Bergmann wrote: > > > > On Thu, Jan 7, 2021 at 2:37 PM Russell King - ARM Linux admin > > I appreciate Arnd pointing out "--std=gnu11", though. What are the > actual relevant language improvements? > > Variable declarations in for-loops is the only one I can think of. I > think that would clean up some code (and some macros), but might not > be compelling on its own. I think that was the main one, as most of --std=c11 is already part of --std=gnu89 as a gnu extension. There were a few things that came up with clang porting, as clang is somewhat closer to gnu11 than to gnu89, but I don't remember exactly what that was. I would still like to improve READ_ONCE()/get_user()/cmpxchg() further using __auto_type and _Generic where possible, but I think that was already supported in gcc-4.9, and does not require gcc-5. Arnd _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel