From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-1459510-1523021859-6-12014946197898033327 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.25, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='US', FromHeader='org', MailFrom='org' X-Spam-charsets: plain='UTF-8' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=fm2; t= 1523021859; b=SlHC5ObV+jPqavnZzbIWuuGu4JsU584LOyEhmNcE7Zofb44kMi UGsE7ZcPga8zMX/jyiXiMeAs+bInYxBPg5P+Wlh3WppNd2wx3Uo6to7JfL9ChPdD l7HcCB/286suhj5/vtsusQq7eSDApNIOQrV4/l03kGhaRvxkE/h+XavY8QDVIlG0 bq7198ffZJO/raweRpRw1FD2be+wEOpPLGQbcPhdGVIDoXuDYAmkPt6q9EzPc8au SxIs//D1h9YQao61aTB947urT4nGczKUdz+b44+OA6TQyz99IhRakbaw2uv+O9mG TZ0248UBtQIZBRoIaObacmkKe6OdPm+IdUvA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-type:sender :list-id; s=fm2; t=1523021859; bh=7xmF2HzUa2Mzvqpk8nDLoCqDNY4O00 53JiYHLhpU0TY=; b=sa5ZqBjVX6dxZStgprifai2hDpGounj6qMu44eYAg/f1Q6 1i5pNBWh9OgUprpUS2Lk8G2K49bO4AIsl3U3yZsL5moXccRGdFYuAme5jhDxallK HrAlTb6QOqp9oQ8NS/inYr4IVSi4NohDu9BnT1lr91L99S2DYThd7i3pD5CJrpa2 IUC537S9kOKL2cyTWXns59q9K0HDN/PEhTelnEAeyn0FHSRpFtSU0RLGzTFIiSNc Y+l9YEBOywy6F7sUR6ni5zLWyTs9IvMXsPi3HxOO5vr9FhmeZy1maPtg0DpQVeo6 7i9dNQ8uHLLXaz88903J7wYGvSGNduWVckjPJGmA== ARC-Authentication-Results: i=1; mx3.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-cm=none score=0; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes; x-vs=clean score=-100 state=0 Authentication-Results: mx3.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-cm=none score=0; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes; x-vs=clean score=-100 state=0 X-ME-VSCategory: clean X-CM-Envelope: MS4wfE+uaYZ3rpQP1jCMWS3A1OqZ3P1FoZLUHluJ2UmFmnt688ONM7YwGDjqisrn4l9r0mkQfOwR0NB6wkOvainIvNTd8cIkR1t6mI4iZXtM0WM8yWEfelfP f1qzdkyDmWNxMqK+HFJhc7rBbzd1lBNYfKF7pZQS0S2XrOCgfzpkUnCKGXhfEFp+IeLxzOaWywtNDJgy0V9K+9TOvycJeimxzKExbDdZ0ekihs0zkYgk9dYA X-CM-Analysis: v=2.3 cv=Tq3Iegfh c=1 sm=1 tr=0 a=UK1r566ZdBxH71SXbqIOeA==:117 a=UK1r566ZdBxH71SXbqIOeA==:17 a=IkcTkHD0fZMA:10 a=Kd1tUaAdevIA:10 a=7CQSdrXTAAAA:8 a=KKAkSRfTAAAA:8 a=1XWaLZrsAAAA:8 a=ag1SF4gXAAAA:8 a=0WtUairGdEF_BEUKMhkA:9 a=QEXdDO2ut3YA:10 a=a-qgeE7W1pNrGK8U0ZQC:22 a=cvBusfyB2V15izCimMoJ:22 a=Yupwre4RP9_Eg_Bd0iYG:22 X-ME-CMScore: 0 X-ME-CMCategory: none Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932278AbeDFNhg (ORCPT ); Fri, 6 Apr 2018 09:37:36 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:32884 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932231AbeDFNhe (ORCPT ); Fri, 6 Apr 2018 09:37:34 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg Kroah-Hartman , Marc Zyngier , Will Deacon , Catalin Marinas , Greg Hackmann , Alex Shi , Mark Rutland Subject: [PATCH 4.9 074/102] arm64: Force KPTI to be disabled on Cavium ThunderX Date: Fri, 6 Apr 2018 15:23:55 +0200 Message-Id: <20180406084341.914967207@linuxfoundation.org> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180406084331.507038179@linuxfoundation.org> References: <20180406084331.507038179@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Marc Zyngier commit 6dc52b15c4a4 upstream. Cavium ThunderX's erratum 27456 results in a corruption of icache entries that are loaded from memory that is mapped as non-global (i.e. ASID-tagged). As KPTI is based on memory being mapped non-global, let's prevent it from kicking in if this erratum is detected. Signed-off-by: Marc Zyngier [will: Update comment] Signed-off-by: Will Deacon Signed-off-by: Catalin Marinas [Alex: use cpus_have_cap as cpus_have_const_cap doesn't exist in v4.9] Signed-off-by: Alex Shi [v4.9 backport] Signed-off-by: Mark Rutland [v4.9 backport] Tested-by: Will Deacon Tested-by: Greg Hackmann Signed-off-by: Greg Kroah-Hartman --- arch/arm64/kernel/cpufeature.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -753,12 +753,23 @@ static int __kpti_forced; /* 0: not forc static bool unmap_kernel_at_el0(const struct arm64_cpu_capabilities *entry, int __unused) { + char const *str = "command line option"; u64 pfr0 = read_system_reg(SYS_ID_AA64PFR0_EL1); - /* Forced on command line? */ + /* + * For reasons that aren't entirely clear, enabling KPTI on Cavium + * ThunderX leads to apparent I-cache corruption of kernel text, which + * ends as well as you might imagine. Don't even try. + */ + if (cpus_have_cap(ARM64_WORKAROUND_CAVIUM_27456)) { + str = "ARM64_WORKAROUND_CAVIUM_27456"; + __kpti_forced = -1; + } + + /* Forced? */ if (__kpti_forced) { - pr_info_once("kernel page table isolation forced %s by command line option\n", - __kpti_forced > 0 ? "ON" : "OFF"); + pr_info_once("kernel page table isolation forced %s by %s\n", + __kpti_forced > 0 ? "ON" : "OFF", str); return __kpti_forced > 0; }