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=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, 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 F2D86C4727D for ; Fri, 25 Sep 2020 12:38:18 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 624FB21D91 for ; Fri, 25 Sep 2020 12:38:18 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 624FB21D91 Authentication-Results: mail.kernel.org; dmarc=none (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 B3AC06B0098; Fri, 25 Sep 2020 08:38:17 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id AEA8D6B0099; Fri, 25 Sep 2020 08:38:17 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A00F76B009A; Fri, 25 Sep 2020 08:38:17 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0112.hostedemail.com [216.40.44.112]) by kanga.kvack.org (Postfix) with ESMTP id 8B5E86B0098 for ; Fri, 25 Sep 2020 08:38:17 -0400 (EDT) Received: from smtpin16.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 47ABF181AE867 for ; Fri, 25 Sep 2020 12:38:17 +0000 (UTC) X-FDA: 77301536634.16.crook77_180e3ff27167 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin16.hostedemail.com (Postfix) with ESMTP id 1FDD010113318 for ; Fri, 25 Sep 2020 12:38:17 +0000 (UTC) X-HE-Tag: crook77_180e3ff27167 X-Filterd-Recvd-Size: 2549 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf06.hostedemail.com (Postfix) with ESMTP for ; Fri, 25 Sep 2020 12:38:16 +0000 (UTC) Received: from gaia (unknown [31.124.44.166]) (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 200A721D7A; Fri, 25 Sep 2020 12:38:12 +0000 (UTC) Date: Fri, 25 Sep 2020 13:38:10 +0100 From: Catalin Marinas To: Vincenzo Frascino Cc: Andrey Konovalov , 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 Subject: Re: [PATCH v3 29/39] arm64: mte: Switch GCR_EL1 in kernel entry and exit Message-ID: <20200925123810.GL4846@gaia> References: <4e503a54297cf46ea1261f43aa325c598d9bd73e.1600987622.git.andreyknvl@google.com> <20200925113433.GF4846@gaia> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: 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 Fri, Sep 25, 2020 at 12:50:23PM +0100, Vincenzo Frascino wrote: > On 9/25/20 12:34 PM, Catalin Marinas wrote: > > On Fri, Sep 25, 2020 at 12:50:36AM +0200, Andrey Konovalov wrote: > >> + /* > >> + * Calculate and set the exclude mask preserving > >> + * the RRND (bit[16]) setting. > >> + */ > >> + mrs_s \tmp2, SYS_GCR_EL1 > >> + bfi \tmp2, \tmp, #0, #16 > >> + msr_s SYS_GCR_EL1, \tmp2 > >> + isb > >> +1: > >> +#endif > >> + .endm > >> + > >> + .macro mte_set_kernel_gcr, tsk, tmp, tmp2 > > > > What's the point of a 'tsk' argument here? > > It is unused. I kept the interface same in between kernel and user. > I can either add a comment or remove it. Which one do you prefer? Please remove it. Having the same interface is more confusing since you have a single kernel gcr_excl but multiple user gcr_excl. -- Catalin