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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 5017DC2BB55 for ; Thu, 16 Apr 2020 12:49:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2E8C821973 for ; Thu, 16 Apr 2020 12:49:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587041380; bh=rQFw7uHZtK1V/T4CiIC4tQ899MpaJHNAwzqsJ4CngmU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=ZIZ/VRRasN4yK1aftt1k5HjN4TTABTQiwSIVM1oLx8C3H+yqALsxvn/nZ3EgAP92s ppd0Kv+wF55VvABu+T1kynCvqjODOjmQ6dof/O5/P9ZYklBOjCwQ8DDIxlqx/EfSdY Cr45GdyTPVGa+qx8c8yaWAiNiosHGQxJ+G06Z8X8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2894543AbgDPMtf (ORCPT ); Thu, 16 Apr 2020 08:49:35 -0400 Received: from mail.kernel.org ([198.145.29.99]:50890 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2894515AbgDPMtF (ORCPT ); Thu, 16 Apr 2020 08:49:05 -0400 Received: from willie-the-truck (236.31.169.217.in-addr.arpa [217.169.31.236]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 92028208E4; Thu, 16 Apr 2020 12:49:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587041344; bh=rQFw7uHZtK1V/T4CiIC4tQ899MpaJHNAwzqsJ4CngmU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=iDAIbZNBoZRv8qIU0jr4LVPMGxXIUHcViCvUwImIZjGHDArrKPy94zfX45DK0nWdh N06rHaUtvoz1GIAWL2P6q90fLJ4kZEngITab5TR04rgHw1KSMnYQt6rh9xr3eW9N9d iefMEwn/6Q18J3k9Um553PKsohEHW4/nn/pEU1jo= Date: Thu, 16 Apr 2020 13:48:59 +0100 From: Will Deacon To: Christian Borntraeger Cc: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, kernel-team@android.com, Michael Ellerman , Peter Zijlstra , Linus Torvalds , Segher Boessenkool , Luc Van Oostenryck , Arnd Bergmann , Peter Oberparleiter , Masahiro Yamada , Nick Desaulniers Subject: Re: [PATCH v3 00/12] Rework READ_ONCE() to improve codegen Message-ID: <20200416124858.GA32685@willie-the-truck> References: <20200415165218.20251-1-will@kernel.org> <809e006e-6641-c252-53a1-cc4479d2ca89@de.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <809e006e-6641-c252-53a1-cc4479d2ca89@de.ibm.com> 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 Thu, Apr 16, 2020 at 02:30:36PM +0200, Christian Borntraeger wrote: > > On 15.04.20 18:52, Will Deacon wrote: > > Hi everyone, > > > > This is version three of the patches I previously posted for improving > > the code generation of READ_ONCE() and moving the minimum GCC version > > to 4.8: > > > > RFC: https://lore.kernel.org/lkml/20200110165636.28035-1-will@kernel.org > > v2: https://lore.kernel.org/lkml/20200123153341.19947-1-will@kernel.org > > > > Although v2 was queued up by Peter in -tip, it was found to break the > > build for m68k and sparc32. We fixed m68k during the merge window and > > I've since posted patches to fix sparc32 here: > > > > https://lore.kernel.org/lkml/20200414214011.2699-1-will@kernel.org > > > > This series is a refresh on top of 5.7-rc1, the main changes being: > > > > * Fix another issue where 'const' is assigned to non-const via > > WRITE_ONCE(), this time in the tls code > > > > * Fix READ_ONCE_NOCHECK() abuse in arm64 checksum code > > > > * Added Reviewed-bys and Acks from v2 > > > > Hopefully this can be considered for 5.8, along with the sparc32 changes. > > > > Cheers, > > > > Will > > > > Cc: Michael Ellerman > > Cc: Peter Zijlstra > > Cc: Linus Torvalds > > Cc: Segher Boessenkool > > Cc: Christian Borntraeger > > Cc: Luc Van Oostenryck > > Cc: Arnd Bergmann > > Cc: Peter Oberparleiter > > Cc: Masahiro Yamada > > Cc: Nick Desaulniers > > > > I gave this series a try and s390 seems to compile fine and it also seems to > properly compile the the ipte_unlock_siif function in arch/s390/kvm/gaccess.c > This function was miscompiled with gcc4.6 and the trigger for replacing > ACCESS_ONCE with READ_ONCE That's good to hear, thanks Christian! Will