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=-10.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 1384CC433E1 for ; Thu, 27 Aug 2020 15:23:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DB3DA2087D for ; Thu, 27 Aug 2020 15:23:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727020AbgH0PXb (ORCPT ); Thu, 27 Aug 2020 11:23:31 -0400 Received: from foss.arm.com ([217.140.110.172]:57092 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728465AbgH0L36 (ORCPT ); Thu, 27 Aug 2020 07:29:58 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id AD5041045; Thu, 27 Aug 2020 04:03:44 -0700 (PDT) Received: from [192.168.1.190] (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 858883F68F; Thu, 27 Aug 2020 04:03:42 -0700 (PDT) Subject: Re: [PATCH 26/35] kasan, arm64: Enable TBI EL1 To: Catalin Marinas , Andrey Konovalov Cc: Dmitry Vyukov , kasan-dev@googlegroups.com, Andrey Ryabinin , Alexander Potapenko , Marco Elver , Evgenii Stepanov , Elena Petrova , Branislav Rankov , Kevin Brodsky , Will Deacon , Andrew Morton , linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <518da1e5169a4e343caa3c37feed5ad551b77a34.1597425745.git.andreyknvl@google.com> <20200827104033.GF29264@gaia> From: Vincenzo Frascino Message-ID: <9c53dfaa-119e-b12e-1a91-1f67f4aef503@arm.com> Date: Thu, 27 Aug 2020 12:05:55 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20200827104033.GF29264@gaia> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 8/27/20 11:40 AM, Catalin Marinas wrote: > On Fri, Aug 14, 2020 at 07:27:08PM +0200, Andrey Konovalov wrote: >> diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S >> index 152d74f2cc9c..6880ddaa5144 100644 >> --- a/arch/arm64/mm/proc.S >> +++ b/arch/arm64/mm/proc.S >> @@ -38,7 +38,7 @@ >> /* PTWs cacheable, inner/outer WBWA */ >> #define TCR_CACHE_FLAGS TCR_IRGN_WBWA | TCR_ORGN_WBWA >> >> -#ifdef CONFIG_KASAN_SW_TAGS >> +#if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS) >> #define TCR_KASAN_FLAGS TCR_TBI1 >> #else >> #define TCR_KASAN_FLAGS 0 > > I prefer to turn TBI1 on only if MTE is present. So on top of the v8 > user series, just do this in __cpu_setup. > Not sure I understand... Enabling TBI1 only if MTE is present would break KASAN_SW_TAGS which is based on TBI1 but not on MTE. -- Regards, Vincenzo