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=-8.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 A147FC5519F for ; Sat, 14 Nov 2020 12:49:30 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 308352222C for ; Sat, 14 Nov 2020 12:49:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="Wh9XWbvs" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 308352222C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=dvuMYYrshaBYwY+BLSiGCFHgnL4U2mtKdsnMINN7FYU=; b=Wh9XWbvs8io0htQjaDG4iALsE E69lbyBsSKQyD68x9POfApBBCEl+GK5xpf/M2Zl/PC8iCgwXRbRvMx1Qp/YtnGMU03KrfG0kbBd4T AEmfM/j4dNFJy/6QC/awSvAncTuPoP+bVhsEHB/LQiW5tmBMQMxeIoPW5VTOHvdp5S3oZsZSHZSVM cDBY2To/qRo5BiKuFpaiDpLvs0JMATI37kaTq/eQ41rMqSCjanVDzlHlAQiH0Xwk9rsDIznFzjcrt eh0X2cvTURj9UyG1NUcY/QjU+/da6GAq27WKpwUPhhJGyI7TBoUXEsUDCziAIdOu7pBq/4Bpf+na0 CCcGY7f/w==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kduyK-0005dn-Hw; Sat, 14 Nov 2020 12:48:04 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kduyH-0005dS-MQ for linux-arm-kernel@lists.infradead.org; Sat, 14 Nov 2020 12:48:02 +0000 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 804B82222C; Sat, 14 Nov 2020 12:47:58 +0000 (UTC) Date: Sat, 14 Nov 2020 12:47:56 +0000 From: Catalin Marinas To: Andrey Konovalov Subject: Re: [PATCH mm v10 28/42] arm64: kasan: Allow enabling in-kernel MTE Message-ID: <20201114124755.GD2837@gaia> References: <123c654a82018611d38af8c83d1e90c16558ce52.1605305705.git.andreyknvl@google.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <123c654a82018611d38af8c83d1e90c16558ce52.1605305705.git.andreyknvl@google.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201114_074801_832116_A4EC4717 X-CRM114-Status: GOOD ( 18.81 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arm-kernel@lists.infradead.org, Marco Elver , Kevin Brodsky , Will Deacon , Branislav Rankov , kasan-dev@googlegroups.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Alexander Potapenko , Evgenii Stepanov , Andrey Ryabinin , Andrew Morton , Vincenzo Frascino , Dmitry Vyukov Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Nov 13, 2020 at 11:15:56PM +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_enable_kernel() helper, that enables MTE in > Synchronous mode in EL1 and is intended to be called from KASAN runtime > during initialization. > > The Tag Checking operation causes a synchronous data abort as > a consequence of a tag check fault when MTE is configured in > synchronous mode. > > As part of this change enable match-all tag for EL1 to allow the > kernel to access user pages without faulting. This is required because > the kernel does not have knowledge of the tags set by the user in a > page. > > Note: For MTE, the TCF bit field in SCTLR_EL1 affects only EL1 in a > similar way as TCF0 affects EL0. > > MTE that is built on top of the Top Byte Ignore (TBI) feature hence we > enable it as part of this patch as well. > > Signed-off-by: Vincenzo Frascino > Co-developed-by: Andrey Konovalov > Signed-off-by: Andrey Konovalov Reviewed-by: Catalin Marinas _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel