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=-8.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,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 8F273C56202 for ; Thu, 12 Nov 2020 09:44:04 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 1B33621D40 for ; Thu, 12 Nov 2020 09:44:04 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1B33621D40 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 8FDF86B0036; Thu, 12 Nov 2020 04:44:03 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 888066B005D; Thu, 12 Nov 2020 04:44:03 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 701666B0068; Thu, 12 Nov 2020 04:44:03 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0243.hostedemail.com [216.40.44.243]) by kanga.kvack.org (Postfix) with ESMTP id 3B74E6B0036 for ; Thu, 12 Nov 2020 04:44:03 -0500 (EST) Received: from smtpin02.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id CC1DB87D8 for ; Thu, 12 Nov 2020 09:44:02 +0000 (UTC) X-FDA: 77475279924.02.spoon14_4d164fe27305 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin02.hostedemail.com (Postfix) with ESMTP id A1F8310097AA0 for ; Thu, 12 Nov 2020 09:44:02 +0000 (UTC) X-HE-Tag: spoon14_4d164fe27305 X-Filterd-Recvd-Size: 2634 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf15.hostedemail.com (Postfix) with ESMTP for ; Thu, 12 Nov 2020 09:44:02 +0000 (UTC) Received: from gaia (unknown [2.26.170.190]) (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 F12DD21D40; Thu, 12 Nov 2020 09:43:56 +0000 (UTC) Date: Thu, 12 Nov 2020 09:43:54 +0000 From: Catalin Marinas To: Andrey Konovalov Cc: Will Deacon , Vincenzo Frascino , Dmitry Vyukov , Andrey Ryabinin , Alexander Potapenko , Marco Elver , Evgenii Stepanov , Branislav Rankov , Kevin Brodsky , Andrew Morton , kasan-dev@googlegroups.com, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v9 30/44] arm64: kasan: Allow enabling in-kernel MTE Message-ID: <20201112094354.GF29613@gaia> References: <5ce2fc45920e59623a4a9d8d39b6c96792f1e055.1605046192.git.andreyknvl@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5ce2fc45920e59623a4a9d8d39b6c96792f1e055.1605046192.git.andreyknvl@google.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, Nov 10, 2020 at 11:10:27PM +0100, Andrey Konovalov wrote: > From: Vincenzo Frascino > > Hardware tag-based KASAN relies on Memory Tagging Extension (MTE) > feature and requires it to be enabled. MTE supports > > This patch adds a new mte_init_tags() helper, that enables MTE in > Synchronous mode in EL1 and is intended to be called from KASAN runtime > during initialization. There's no mte_init_tags() in this function. > diff --git a/arch/arm64/kernel/mte.c b/arch/arm64/kernel/mte.c > index 600b26d65b41..7f477991a6cf 100644 > --- a/arch/arm64/kernel/mte.c > +++ b/arch/arm64/kernel/mte.c > @@ -129,6 +129,13 @@ void *mte_set_mem_tag_range(void *addr, size_t size, u8 tag) > return ptr; > } > > +void mte_enable(void) > +{ > + /* Enable MTE Sync Mode for EL1. */ > + sysreg_clear_set(sctlr_el1, SCTLR_ELx_TCF_MASK, SCTLR_ELx_TCF_SYNC); > + isb(); > +} Nitpick: maybe rename this to mte_enable_kernel() since MTE is already enabled for user apps. -- Catalin