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=-7.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 E1615C43441 for ; Wed, 21 Nov 2018 19:11:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A7EC4214DB for ; Wed, 21 Nov 2018 19:11:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="a9jI9tDa" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A7EC4214DB Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388908AbeKVFqj (ORCPT ); Thu, 22 Nov 2018 00:46:39 -0500 Received: from mail.kernel.org ([198.145.29.99]:41930 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730565AbeKVFqh (ORCPT ); Thu, 22 Nov 2018 00:46:37 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (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 D200021582; Wed, 21 Nov 2018 19:11:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1542827464; bh=C8O7pqoxdYUvwPTuY1OJxyMCsN4IYSV8HH7NPAdCHnE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=a9jI9tDa3uXHZURr00bi5SfbCVsTPtpYf0tIF6jzchQs1if/mTxW7/RBFuvVZIbH4 CR8mJvM3PmDLVdV/K2/b0oZjUwj+QYm3bMrXmS/WsvY4BX+dsrbCYz20Bk03Ypv12v kqSeFhxq6ARZuoq8FUAnEf73X7caLihjkB+ivTvQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Russell King , Florian Fainelli , Tony Lindgren , "David A. Long" Subject: [PATCH 4.9 42/59] ARM: spectre-v2: add Cortex A8 and A15 validation of the IBE bit Date: Wed, 21 Nov 2018 20:06:57 +0100 Message-Id: <20181121183509.920309307@linuxfoundation.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181121183508.262873520@linuxfoundation.org> References: <20181121183508.262873520@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Russell King Commit e388b80288aade31135aca23d32eee93dd106795 upstream. When the branch predictor hardening is enabled, firmware must have set the IBE bit in the auxiliary control register. If this bit has not been set, the Spectre workarounds will not be functional. Add validation that this bit is set, and print a warning at alert level if this is not the case. Signed-off-by: Russell King Reviewed-by: Florian Fainelli Boot-tested-by: Tony Lindgren Reviewed-by: Tony Lindgren Signed-off-by: David A. Long Signed-off-by: Greg Kroah-Hartman --- arch/arm/mm/Makefile | 2 +- arch/arm/mm/proc-v7-bugs.c | 36 ++++++++++++++++++++++++++++++++++++ arch/arm/mm/proc-v7.S | 4 ++-- 3 files changed, 39 insertions(+), 3 deletions(-) create mode 100644 arch/arm/mm/proc-v7-bugs.c --- a/arch/arm/mm/Makefile +++ b/arch/arm/mm/Makefile @@ -94,7 +94,7 @@ obj-$(CONFIG_CPU_MOHAWK) += proc-mohawk. obj-$(CONFIG_CPU_FEROCEON) += proc-feroceon.o obj-$(CONFIG_CPU_V6) += proc-v6.o obj-$(CONFIG_CPU_V6K) += proc-v6.o -obj-$(CONFIG_CPU_V7) += proc-v7.o +obj-$(CONFIG_CPU_V7) += proc-v7.o proc-v7-bugs.o obj-$(CONFIG_CPU_V7M) += proc-v7m.o AFLAGS_proc-v6.o :=-Wa,-march=armv6 --- /dev/null +++ b/arch/arm/mm/proc-v7-bugs.c @@ -0,0 +1,36 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include + +static __maybe_unused void cpu_v7_check_auxcr_set(bool *warned, + u32 mask, const char *msg) +{ + u32 aux_cr; + + asm("mrc p15, 0, %0, c1, c0, 1" : "=r" (aux_cr)); + + if ((aux_cr & mask) != mask) { + if (!*warned) + pr_err("CPU%u: %s", smp_processor_id(), msg); + *warned = true; + } +} + +static DEFINE_PER_CPU(bool, spectre_warned); + +static void check_spectre_auxcr(bool *warned, u32 bit) +{ + if (IS_ENABLED(CONFIG_HARDEN_BRANCH_PREDICTOR) && + cpu_v7_check_auxcr_set(warned, bit, + "Spectre v2: firmware did not set auxiliary control register IBE bit, system vulnerable\n"); +} + +void cpu_v7_ca8_ibe(void) +{ + check_spectre_auxcr(this_cpu_ptr(&spectre_warned), BIT(6)); +} + +void cpu_v7_ca15_ibe(void) +{ + check_spectre_auxcr(this_cpu_ptr(&spectre_warned), BIT(0)); +} --- a/arch/arm/mm/proc-v7.S +++ b/arch/arm/mm/proc-v7.S @@ -564,7 +564,7 @@ __v7_setup_stack: globl_equ cpu_ca8_do_suspend, cpu_v7_do_suspend globl_equ cpu_ca8_do_resume, cpu_v7_do_resume #endif - define_processor_functions ca8, dabort=v7_early_abort, pabort=v7_pabort, suspend=1 + define_processor_functions ca8, dabort=v7_early_abort, pabort=v7_pabort, suspend=1, bugs=cpu_v7_ca8_ibe @ Cortex-A9 - needs more registers preserved across suspend/resume @ and bpiall switch_mm for hardening @@ -597,7 +597,7 @@ __v7_setup_stack: globl_equ cpu_ca15_suspend_size, cpu_v7_suspend_size globl_equ cpu_ca15_do_suspend, cpu_v7_do_suspend globl_equ cpu_ca15_do_resume, cpu_v7_do_resume - define_processor_functions ca15, dabort=v7_early_abort, pabort=v7_pabort, suspend=1 + define_processor_functions ca15, dabort=v7_early_abort, pabort=v7_pabort, suspend=1, bugs=cpu_v7_ca15_ibe #ifdef CONFIG_CPU_PJ4B define_processor_functions pj4b, dabort=v7_early_abort, pabort=v7_pabort, suspend=1 #endif