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=-10.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 8BAEFC433E0 for ; Tue, 9 Mar 2021 10:07:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 50B5665259 for ; Tue, 9 Mar 2021 10:07:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230111AbhCIKHT (ORCPT ); Tue, 9 Mar 2021 05:07:19 -0500 Received: from foss.arm.com ([217.140.110.172]:50832 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229815AbhCIKGq (ORCPT ); Tue, 9 Mar 2021 05:06:46 -0500 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 3167B31B; Tue, 9 Mar 2021 02:06:45 -0800 (PST) Received: from [10.37.8.8] (unknown [10.37.8.8]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 9EFC73F71B; Tue, 9 Mar 2021 02:06:42 -0800 (PST) Subject: Re: [PATCH v14 0/8] arm64: ARMv8.5-A: MTE: Add async mode support To: Andrey Konovalov Cc: Linux ARM , LKML , kasan-dev , Andrew Morton , Catalin Marinas , Will Deacon , Dmitry Vyukov , Andrey Ryabinin , Alexander Potapenko , Marco Elver , Evgenii Stepanov , Branislav Rankov , Lorenzo Pieralisi References: <20210308161434.33424-1-vincenzo.frascino@arm.com> From: Vincenzo Frascino Message-ID: <723ec86a-75be-e0e3-e4a9-b3d40d69e238@arm.com> Date: Tue, 9 Mar 2021 10:11:07 +0000 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: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Andrey, On 3/8/21 9:02 PM, Andrey Konovalov wrote: > On Mon, Mar 8, 2021 at 5:14 PM Vincenzo Frascino > wrote: >> >> This patchset implements the asynchronous mode support for ARMv8.5-A >> Memory Tagging Extension (MTE), which is a debugging feature that allows >> to detect with the help of the architecture the C and C++ programmatic >> memory errors like buffer overflow, use-after-free, use-after-return, etc. >> >> MTE is built on top of the AArch64 v8.0 virtual address tagging TBI >> (Top Byte Ignore) feature and allows a task to set a 4 bit tag on any >> subset of its address space that is multiple of a 16 bytes granule. MTE >> is based on a lock-key mechanism where the lock is the tag associated to >> the physical memory and the key is the tag associated to the virtual >> address. >> When MTE is enabled and tags are set for ranges of address space of a task, >> the PE will compare the tag related to the physical memory with the tag >> related to the virtual address (tag check operation). Access to the memory >> is granted only if the two tags match. In case of mismatch the PE will raise >> an exception. >> >> The exception can be handled synchronously or asynchronously. When the >> asynchronous mode is enabled: >> - Upon fault the PE updates the TFSR_EL1 register. >> - The kernel detects the change during one of the following: >> - Context switching >> - Return to user/EL0 >> - Kernel entry from EL1 >> - Kernel exit to EL1 >> - If the register has been updated by the PE the kernel clears it and >> reports the error. >> >> The series is based on linux-next/akpm. >> >> To simplify the testing a tree with the new patches on top has been made >> available at [1]. >> >> [1] https://git.gitlab.arm.com/linux-arm/linux-vf.git mte/v12.async.akpm > > Hi Vincenzo, > > As previously discussed, here's the tree with tests support added to > this series: > > https://github.com/xairy/linux/tree/vf-v12.async.akpm-tests > > Please take a look at the last two patches. Feel free to include them > into v15 if they look good. > > Thanks! > Thank you for this. I will definitely have a look and include them. Based on the review process, I am planning to have another version early next week. -- Regards, Vincenzo