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=-2.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no 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 26A50C433DF for ; Wed, 1 Jul 2020 17:17:42 +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 E3A7E20747 for ; Wed, 1 Jul 2020 17:17:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="wZj6XenV" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E3A7E20747 Authentication-Results: mail.kernel.org; dmarc=none (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=igtAg09k03yisgB20RIB+zpaC5FxDX+fRdWXYQIoxe8=; b=wZj6XenV17IDyNrR94FkogMaa 9UZxzXfbJ3NOEsTjHEqgMe+TDIhDYzIjsGW8CxMaCMYHUxTLsfaxgnf/sRuhTuC2HVOr6QgZgZWnR riE8/MZLJ8vxemw4TazmpVhvhiGFCfIMOrl5i7s2FOjQabEhfLOpkFrTUjCssneHbRYwaOVzDdKAY Fy+zAxfF3192nteos9N3sCzwMKlcIfI07IN0XlUa/epTE/HB/Nk4BXDlYOIgnSxXVzv+xoUoYtOdS kfJ0qy6ZwHM12H3/Buz3fglfeY7qMOl0/AVLtgS17lImEcF1SoKtA0lqofJpH808lPtZe7ElHYI4w yN718NmoA==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jqgLK-0007VN-Bm; Wed, 01 Jul 2020 17:16:18 +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 1jqgLH-0007US-Kq for linux-arm-kernel@lists.infradead.org; Wed, 01 Jul 2020 17:16:16 +0000 Received: from gaia (unknown [95.146.230.158]) (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 DB9522078A; Wed, 1 Jul 2020 17:16:11 +0000 (UTC) Date: Wed, 1 Jul 2020 18:16:09 +0100 From: Catalin Marinas To: Luis Machado Subject: Re: [PATCH v5 19/25] arm64: mte: Add PTRACE_{PEEK,POKE}MTETAGS support Message-ID: <20200701171549.GF5191@gaia> References: <20200624175244.25837-1-catalin.marinas@arm.com> <20200624175244.25837-20-catalin.marinas@arm.com> <7fd536af-f9fa-aa10-a4c3-001e80dd7d7b@linaro.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <7fd536af-f9fa-aa10-a4c3-001e80dd7d7b@linaro.org> 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-20200701_131615_744494_FDB601F7 X-CRM114-Status: GOOD ( 15.38 ) 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-arch@vger.kernel.org, Omair Javaid , Szabolcs Nagy , Andrey Konovalov , Kevin Brodsky , Peter Collingbourne , linux-mm@kvack.org, Alan Hayward , Andrew Morton , Vincenzo Frascino , Will Deacon , Dave P Martin , linux-arm-kernel@lists.infradead.org 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 Hi Luis, On Thu, Jun 25, 2020 at 02:10:10PM -0300, Luis Machado wrote: > I have one point below I wanted to clarify regarding > PEEKMTETAGS/POKEMTETAGS. > > But before that, I've pushed v2 of the MTE series for GDB here: > > https://sourceware.org/git/?p=binutils-gdb.git;a=shortlog;h=refs/heads/users/luisgpm/aarch64-mte-v2 > > That series adds sctlr and gcr registers to the NT_ARM_MTE (still using a > dummy value of 0x407) register set. It would be nice if the Linux Kernel and > the debuggers were in sync in terms of supporting this new register set. GDB > assumes the register set exists if HWCAP2_MTE is there. > > So, if we want to adjust the register set, we should probably consider doing > that now. That prevents the situation where debuggers would need to do > another check to confirm NT_ARM_MTE is exported. I'd rather avoid that. I'm happy to do this before merging, though we need to agree on the semantics. Do you need both read and write access? Also wondering whether the prctl() value would be a better option than the raw register bits (well, not entirely raw, masking out the irrelevant part). -- Catalin _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel