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=-5.2 required=3.0 tests=BAYES_00,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 9C06DC2D0A3 for ; Thu, 12 Nov 2020 12:55:27 +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 385EB21D7F for ; Thu, 12 Nov 2020 12:55:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="fnhS/UGj" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 385EB21D7F 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=/5T/QT0f28eYMIxY4C2V40+Ulf6rjsutxjwMOxjba4s=; b=fnhS/UGj2GAqgpkXtW/Ol2NhC pMQOu6HqBqloMmNZPXxQMv0yf2fDebUD3Qf0Trt4716w9Us33dnpiTZ+lU7f1/2EdbMelFBkeHLZx KwAP89E4Gy+dyfEHC6XYuUjtHog50VHajlqh2fgoXViSs8t9a/0uzrl6CjCh0jpq7bklvQOvXK9wK XSkEtjyzvJDYBH8z3Q225/rv1CH2GpaasjFynCsBzXJ5HcxwnWxgeUHCvOpIIod48DNupZuHXxn5u l4i8cUMJCk/65lzvg4/9WH246bxqu78AuBjbtEFJfo6Pu4hGXmazf4cQ/WOW360I2TB07EUyL0XS2 WcGYdQ6EA==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kdC7y-0005Kb-VY; Thu, 12 Nov 2020 12:55:03 +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 1kdC7w-0005JZ-BS for linux-arm-kernel@lists.infradead.org; Thu, 12 Nov 2020 12:55:01 +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 B5E4521D7F; Thu, 12 Nov 2020 12:54:56 +0000 (UTC) Date: Thu, 12 Nov 2020 12:54:54 +0000 From: Catalin Marinas To: Marco Elver Subject: Re: [PATCH v2 11/20] kasan: add and integrate kasan boot parameters Message-ID: <20201112125453.GM29613@gaia> References: <20201112113541.GK29613@gaia> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: 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-20201112_075500_477946_C4F3170D X-CRM114-Status: GOOD ( 22.67 ) 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 , Branislav Rankov , Andrey Konovalov , Kevin Brodsky , Will Deacon , LKML , kasan-dev , Linux Memory Management List , Alexander Potapenko , Dmitry Vyukov , Andrey Ryabinin , Andrew Morton , Vincenzo Frascino , Evgenii Stepanov 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 Thu, Nov 12, 2020 at 12:53:58PM +0100, Marco Elver wrote: > On Thu, 12 Nov 2020 at 12:35, Catalin Marinas wrote: > > > > On Tue, Nov 10, 2020 at 11:20:15PM +0100, Andrey Konovalov wrote: > > > Hardware tag-based KASAN mode is intended to eventually be used in > > > production as a security mitigation. Therefore there's a need for finer > > > control over KASAN features and for an existence of a kill switch. > > > > > > This change adds a few boot parameters for hardware tag-based KASAN that > > > allow to disable or otherwise control particular KASAN features. > > > > > > The features that can be controlled are: > > > > > > 1. Whether KASAN is enabled at all. > > > 2. Whether KASAN collects and saves alloc/free stacks. > > > 3. Whether KASAN panics on a detected bug or not. > > > > > > With this change a new boot parameter kasan.mode allows to choose one of > > > three main modes: > > > > > > - kasan.mode=off - KASAN is disabled, no tag checks are performed > > > - kasan.mode=prod - only essential production features are enabled > > > - kasan.mode=full - all KASAN features are enabled > > > > Alternative naming if we want to avoid "production" (in case someone > > considers MTE to be expensive in a production system): > > > > - kasan.mode=off > > - kasan.mode=on > > - kasan.mode=debug > > I believe this was what it was in RFC, and we had a long discussion on > what might be the most intuitive options. Since KASAN is still a > debugging tool for the most part, an "on" mode might imply we get all > the debugging facilities of regular KASAN. However, this is not the > case and misleading. Hence, we decided to be more explicit and avoid > "on". Even better, kasan.mode=fast ;). -- Catalin _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel