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, 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 C0C9CC433E0 for ; Fri, 31 Jul 2020 17:40:26 +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 985E52083B for ; Fri, 31 Jul 2020 17:40:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="t90arOBx"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="U3vYlXFP" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 985E52083B 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=OJUMl1VDQy+iHdrEB8aWW3q54fvDwJ517vIwA1oAC5k=; b=t90arOBxcJPjz8p62CXzj6cFwD /+1go+e02EsACBGWIBD65YP8TnC59iN4r4UVJe/7Hu1wLQdqW6jI2g4lxEY/IuN/fh8Fgp2wLV5Lf lWESfVs3PkDfuMtVFMrmWd9MMxz/fX+4G3hrF89RjWu3gqs0wpDEj88uDR9j8XJ/YVE6rxMprJ+BO WViF4FNUmdoZcDu+TI1BM0QYa5Uy9MW+CDqhoaEb54xftsG+oaiavMAzZ3K2c/sPYAhM5x6ROX2Il oO8mCLArdli2fRems0jkvW/5cVxsICvn1Q3SHCND0UX8snKpHcvtf6j4hTMK47eoMWNSdO3RE/Si7 yNRo7e+w==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1k1YzN-0006ho-G2; Fri, 31 Jul 2020 17:38:37 +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 1k1YzL-0006gY-2X for linux-arm-kernel@lists.infradead.org; Fri, 31 Jul 2020 17:38:36 +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 EA4052083B; Fri, 31 Jul 2020 17:38:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1596217114; bh=mziGqWlK3OXMZW3KJgVR5MelxphI3Rpw7oReUkbJx4E=; h=From:To:Cc:Subject:Date:From; b=U3vYlXFPygLp8Ei2PhbruLLp85xU6QnVCBlhzMMyd/WN0oDVpnAzJvZCt4ja5LNI3 BZ5nPM3BO09XXNFe89SdwCFcAHU/bI58IH8aEviU0xM3PA4mgfAeQbz1gYTXqSRzxc c254LuuHkN8Jy40uLBiycXRfTPKR3c/BQRGVV2qg= 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 1k1YzI-00GaQI-8l; Fri, 31 Jul 2020 18:38:32 +0100 From: Marc Zyngier To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v3 0/2] arm64: Allow erratum 1418040 for late CPUs Date: Fri, 31 Jul 2020 18:38:22 +0100 Message-Id: <20200731173824.107480-1-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_133835_349300_61C380D9 X-CRM114-Status: GOOD ( 13.76 ) 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 * From v2: - Dropped __always_inline again - Simplified logic 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 *** BLURB HERE *** 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 | 34 ++++++++++++++++++++++++++++++++++ 3 files changed, 36 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