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=-6.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,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 15096C4727C for ; Fri, 25 Sep 2020 13:36:15 +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 9062A2076D for ; Fri, 25 Sep 2020 13:36:14 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="o9KOOL1y" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9062A2076D 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:Date:Message-ID:From: References:To:Subject:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=Gbh8BIRVB3j7fDH2H+ljVLU3w8HvJzsHj1+MINOtqeo=; b=o9KOOL1y/g/44FO28EKOL3bTq bsR6oIPaH41thTcs/ZMv8t9V3vW5pZig5Fje/HTcyWg82YuFa9rVUPrquRKwmY4rZk+L4VyVDMESc gjPXvU1YVq0NScZJ2SL9XNfhM2etXRB3co5P/3waWg4UCeqwWCbpkc/3+Kx1MgXB2N319gyGTL2if RUygB+3tmoFCCc+uhmLotCbXVGaLUY77vN+A1GMd7m6QdAN9BGQd6Pfe49R0LWmvWD9xQsEK64xuT 4VLdrSWYFsJLrLCc4Ik1deCbRsoRO8PdiM56EZSFIoAhlJAOaoFHWcfNXhzXN2gsr7NrtWWHeMxRR MP2eNjY9A==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kLnrR-0008Hk-Gp; Fri, 25 Sep 2020 13:34:05 +0000 Received: from foss.arm.com ([217.140.110.172]) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kLnrP-0008Gv-8w for linux-arm-kernel@lists.infradead.org; Fri, 25 Sep 2020 13:34:04 +0000 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 B12AB11B3; Fri, 25 Sep 2020 06:33:59 -0700 (PDT) Received: from [10.37.12.53] (unknown [10.37.12.53]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id EB5953F73B; Fri, 25 Sep 2020 06:33:56 -0700 (PDT) Subject: Re: [PATCH v3 24/39] arm64: mte: Add in-kernel MTE helpers To: Catalin Marinas References: <20200925101558.GB4846@gaia> <20200925125059.GM4846@gaia> From: Vincenzo Frascino Message-ID: Date: Fri, 25 Sep 2020 14:36:29 +0100 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: <20200925125059.GM4846@gaia> Content-Language: en-US X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200925_093403_368272_F6407C57 X-CRM114-Status: GOOD ( 16.49 ) 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 , Elena Petrova , Andrey Konovalov , 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 , 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 9/25/20 1:50 PM, Catalin Marinas wrote: >>>> + */ >>>> +SYM_FUNC_START(mte_assign_mem_tag_range) >>>> + /* if (src == NULL) return; */ >>>> + cbz x0, 2f >>>> + /* if (size == 0) return; */ >>>> + cbz x1, 2f >>> I find these checks unnecessary, as I said a couple of times before, >>> just document the function pre-conditions. They are also incomplete >>> (i.e. you check for NULL but not alignment). >>> >> I thought we agreed to harden the code further, based on [1]. Maybe I >> misunderstood. I am going to remove them and extend the comment in the next version. >> >> [1] >> https://lore.kernel.org/linux-arm-kernel/921c4ed0-b5b5-bc01-5418-c52d80f1af59@arm.com/ > Well, you concluded that but I haven't confirmed ;). Since it's called > from a single place which does the checks already, I don't see the point > in duplicating them. Documenting should be sufficient. Have you ever heard about "tacit consent"? ;) Anw, fine by me, I will add a comment here. -- Regards, Vincenzo _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel