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=-7.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT 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 62CAAC433DF for ; Fri, 31 Jul 2020 08:36:13 +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 2FFF420663 for ; Fri, 31 Jul 2020 08:36:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="Hm201twl"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="LksWSCzy" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2FFF420663 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:MIME-Version:Message-Id:Date:Subject:To:From: Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender :Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Owner; bh=dgcYbFDb2rzK3jxpWQeZe0YTYM/b7tKSWmuN3ExasvU=; b=Hm201twltngUO+O9hgt26PPIvm IndciYNQ44Kb78U3jov23gYJUK5KtPyOtQViLSK8lWRH43/95sGVK7b01g/aXWQlQmqFqsh4dqEWP ZQ+sa3xyNYzZp6vsCa4gEHcivC7e23f2tnoG95vVw6/2hY2OR3tAzzAXvrikQwSjMZs4XcFBVwGnM SYEwYyYeo8mCU5OXSBO18AlsjY2RjfNJ2nMfakkGsHev8NZ/uliGxjZTpqtg1ZXHRA4BhCoErTtrY 92TL6A/zuAH9HwCyIK21cSFxEwwyIgQAhfH7S8TQLFwXQozCOI9NL8bQhCnfP/tuaVheOf9xumVXe ZUy0H3Aw==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1k1QUl-0006xK-IG; Fri, 31 Jul 2020 08:34:27 +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 1k1QUi-0006w2-W7 for linux-arm-kernel@lists.infradead.org; Fri, 31 Jul 2020 08:34:25 +0000 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (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 CEA252072A; Fri, 31 Jul 2020 08:34:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1596184464; bh=DW1QWH1RogyOn7LmPGBBMrzfYYPcvzuHFRpKXib+yeg=; h=From:To:Cc:Subject:Date:From; b=LksWSCzyIIXm6QXGjmVVoLe1bVCFs8/Ow1fJUj/3L+2B7ZaiCHVzR7nNIIA0GPUvc DST9xsd6WCtqdIv7M+r9jL9mfeJeNlVAlOR9QPmMqWP096Su8Q7qlU0YqxLpNd/FxE qsXzRh62873mfALhF/ABxfpAYWq8EoueVk4RVFzM= Received: from 78.163-31-62.static.virginmediabusiness.co.uk ([62.31.163.78] helo=why.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1k1QUg-00GTkD-93; Fri, 31 Jul 2020 09:34:22 +0100 From: Marc Zyngier To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v2 0/2] arm64: Allow erratum 1418040 for late CPUs Date: Fri, 31 Jul 2020 09:33:56 +0100 Message-Id: <20200731083358.50058-1-maz@kernel.org> X-Mailer: git-send-email 2.27.0 MIME-Version: 1.0 X-SA-Exim-Connect-IP: 62.31.163.78 X-SA-Exim-Rcpt-To: linux-arm-kernel@lists.infradead.org, saiprakash.ranjan@codeaurora.org, will@kernel.org, catalin.marinas@arm.com, suzuki.poulose@arm.com, swboyd@chromium.org, dianders@google.com, kernel-team@android.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200731_043425_109786_081FCEBD X-CRM114-Status: GOOD ( 13.65 ) 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: Sai Prakash Ranjan , kernel-team@android.com, Suzuki K Poulose , Catalin Marinas , Stephen Boyd , dianders@google.com, Will Deacon 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 Erratum 1418040 currently prevents a late CPU from booting if none of the early CPUs are affected by it. This is because the handling is implemented as alternatives, and we have already got rid of them by the time userspace onlines a new CPU. A solution to this is to move everything into C code, and rely on static keys instead. Once this is done, the feature can be allowed for late CPUs. Note that CPUs affected by 1418040 also tend to miss AArch32-EL1, meaning they cannot be used as late CPUs when KVM is enabled and that their sibblings have AArch32-EL1. * From v1: - Dropped check for kernel threads - Added comment describing the switching logic - Made the errata handling function __always_inline Marc Zyngier (2): arm64: Move handling of erratum 1418040 into C code arm64: Allow booting of late CPUs affected by erratum 1418040 arch/arm64/kernel/cpu_errata.c | 2 ++ arch/arm64/kernel/entry.S | 21 -------------------- arch/arm64/kernel/process.c | 35 ++++++++++++++++++++++++++++++++++ 3 files changed, 37 insertions(+), 21 deletions(-) -- 2.27.0 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel