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=-16.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham 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 50A09C433E0 for ; Mon, 8 Feb 2021 12:30:18 +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 CE8D064E75 for ; Mon, 8 Feb 2021 12:30:17 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CE8D064E75 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:In-Reply-To:MIME-Version:References:Message-ID: Subject:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=HwX/YU5XNQRIXWqLmadJpbsCRRbSVexkQQipkI+U4Q8=; b=V/1PL8mfjy9OqGprPp2fzg2mO BExLuhkuACrCHkrz7kLr9cuStxwjUuD93poMF6GpMkeEqi1FD7iWdfnzLWLPwjKZSIYIsN1tsFEfV 406Auup0Zx403OKWZI6p9ABiamw4FbubPVCkf0O7tPTcFu+xBGZD6UO3/pnpEPDGftbVCEZfAw8bX UykqJ1B44pi1viODUuNfVK4kHuYfPUu5lbZnd30aVpsJuVN+2G+tcw7MLkBAjBm+SxEUSkgt/O7So 5PeMan78yMeDQGfH5hwM5Vn2SEj5waxRA9cdyWpVwuDXtRoeAIbrGHCjVey1RAvkEAVH1kol8RnhO 3ZxlVcSxg==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1l95f9-0000nd-W9; Mon, 08 Feb 2021 12:29:08 +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 1l95f8-0000nF-JB for linux-arm-kernel@lists.infradead.org; Mon, 08 Feb 2021 12:29:07 +0000 Received: by mail.kernel.org (Postfix) with ESMTPSA id CCE7364E75; Mon, 8 Feb 2021 12:29:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1612787345; bh=JZyoKRE2X+fJ2fOJ47en528lxLoPdoBP579anr6xUV0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ChWEjp5pfKUHfK20e508XjG0mgnhkmJ80zCYqdUBC+HZRu4eaVQ8LBykQJ8HOqAOa KbGDA+13m0Ald7CHnW84p2WGcsZEhAoFBPi5xGKMP3IipP3dCPbUAT+wwu51a6ymXJ Xz7NKfXa9Uf0OhobeD7GBvM0Ah6ycGkGnqarrI16nQLmxyYoO2VvX4nc8NdHZ1wMFH 0Byv+DqA40dRR/UJ2frzrtxQnpO6lDefnD5wliWhaZrzLIHq7OFZjfhzjJ6yOabOUP LSTCt68i77eMJGzobZ31XRC7g/hvtCVhGPXdBiy5oZ7xgxHW9kxVSqBcIL07xgQJSC DSj/2DsXV1f3Q== Date: Mon, 8 Feb 2021 12:29:00 +0000 From: Will Deacon To: Suzuki K Poulose Subject: Re: [PATCH] arm64: Extend workaround for erratum 1024718 to all versions of Cortex-A55 Message-ID: <20210208122859.GA25618@willie-the-truck> References: <20210203230057.3961239-1-suzuki.poulose@arm.com> <20210204095457.GA20361@willie-the-truck> <5a8ea892-98bb-e02e-cced-9ffa7e0bbda9@arm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <5a8ea892-98bb-e02e-cced-9ffa7e0bbda9@arm.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210208_072906_715162_89403C54 X-CRM114-Status: GOOD ( 24.75 ) 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: catalin.marinas@arm.com, Kunihiko Hayashi , James Morse , stable@vger.kernel.org, linux-arm-kernel@lists.infradead.org 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, Feb 05, 2021 at 05:41:05PM +0000, Suzuki K Poulose wrote: > On 2/4/21 9:54 AM, Will Deacon wrote: > > On Wed, Feb 03, 2021 at 11:00:57PM +0000, Suzuki K Poulose wrote: > > > The erratum 1024718 affects Cortex-A55 r0p0 to r2p0. However > > > we apply the work around for r0p0 - r1p0. Unfortunately this > > > won't be fixed for the future revisions for the CPU. Thus > > > extend the work around for all versions of A55, to cover > > > for r2p0 and any future revisions. > > > > > > Cc: stable@vger.kernel.org > > > Cc: Catalin Marinas > > > Cc: Will Deacon > > > Cc: James Morse > > > Cc: Kunihiko Hayashi > > > Signed-off-by: Suzuki K Poulose > > > --- > > > arch/arm64/kernel/cpufeature.c | 2 +- > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c > > > index e99eddec0a46..db400ca77427 100644 > > > --- a/arch/arm64/kernel/cpufeature.c > > > +++ b/arch/arm64/kernel/cpufeature.c > > > @@ -1455,7 +1455,7 @@ static bool cpu_has_broken_dbm(void) > > > /* List of CPUs which have broken DBM support. */ > > > static const struct midr_range cpus[] = { > > > #ifdef CONFIG_ARM64_ERRATUM_1024718 > > > - MIDR_RANGE(MIDR_CORTEX_A55, 0, 0, 1, 0), // A55 r0p0 -r1p0 > > > + MIDR_ALL_VERSIONS(MIDR_CORTEX_A55), > > > > I think we have bigger problems with this erratum, since cpu_has_hw_af() > > doesn't taken this erratum into account at all, meaning that > > arch_faults_on_old_pte() will return the wrong value on any system with an > > A55. > > Please note that we enable HW_AF on these CPUs even with this erratum as > they are not affected. It is only the DBM that we selectively disable. Thus > the AF flag checks are still valid (See __cpu_setup in arch/arm64/mm/proc.S). > Or am I miss something ? Thanks, you're completely right! I'll queue this one then, and update the Kconfig test at the same time. Will _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel