From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on archive.lwn.net X-Spam-Level: X-Spam-Status: No, score=-4.7 required=5.0 tests=DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,RCVD_IN_DNSWL_HI,T_DKIM_INVALID, T_RP_MATCHES_RCVD autolearn=ham autolearn_force=no version=3.4.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by archive.lwn.net (Postfix) with ESMTP id 543867DE78 for ; Mon, 2 Apr 2018 18:16:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753279AbeDBSQN (ORCPT ); Mon, 2 Apr 2018 14:16:13 -0400 Received: from pandora.armlinux.org.uk ([78.32.30.218]:46042 "EHLO pandora.armlinux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753030AbeDBSQL (ORCPT ); Mon, 2 Apr 2018 14:16:11 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2014; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=jYfSrkpv8FOUzemlQoG3h7Mxq7My+IRLeJola3h8FBw=; b=rPxSnY+D9vvGlu/UDQsdl8jnw JOrjCRHpUYwY64HR+fnh746MzeTafNuPMyO2rrHgTkK5RhqxUDTRHsqOjoAaSWWKxCHOR5GmjN9Dk +1LxUByvXSxHe274xYB2r3nm6UlEI6InPsOrNBbQckEIBTLNSCv49x4WxPOEYahgEc4JQ=; Received: from n2100.armlinux.org.uk ([fd8f:7570:feb6:1:214:fdff:fe10:4f86]:55661) by pandora.armlinux.org.uk with esmtpsa (TLSv1.2:ECDHE-RSA-AES128-GCM-SHA256:128) (Exim 4.90_1) (envelope-from ) id 1f33za-0005lE-6j; Mon, 02 Apr 2018 19:15:42 +0100 Received: from linux by n2100.armlinux.org.uk with local (Exim 4.90_1) (envelope-from ) id 1f33zW-0001RK-Q3; Mon, 02 Apr 2018 19:15:39 +0100 Date: Mon, 2 Apr 2018 19:15:37 +0100 From: Russell King - ARM Linux To: Nicolas Pitre Cc: Abbott Liu , kstewart@linuxfoundation.org, tixy@linaro.org, grygorii.strashko@linaro.org, julien.thierry@arm.com, Catalin Marinas , linux@rasmusvillemoes.dk, dhowells@redhat.com, linux-mm@kvack.org, mark.rutland@arm.com, kvmarm@lists.cs.columbia.edu, f.fainelli@gmail.com, Jonathan Corbet , linux-doc@vger.kernel.org, kasan-dev@googlegroups.com, geert@linux-m68k.org, linux-arm-kernel@lists.infradead.org, zhichao.huang@linaro.org, aryabinin@virtuozzo.com, labbott@redhat.com, vladimir.murzin@arm.com, keescook@chromium.org, Arnd Bergmann , marc.zyngier@arm.com, philip@cog.systems, jinb.park7@gmail.com, opendmb@gmail.com, tglx@linutronix.de, dvyukov@google.com, ard.biesheuvel@linaro.org, gregkh@linuxfoundation.org, mawilcox@microsoft.com, linux-kernel@vger.kernel.org, alexander.levin@verizon.com, james.morse@arm.com, kirill.shutemov@linux.intel.com, pombredanne@nexb.com, Andrew Morton , thgarnie@google.com, christoffer.dall@linaro.org Subject: Re: [PATCH v3 5/6] Initialize the mapping of KASan shadow memory Message-ID: <20180402181536.GJ16141@n2100.armlinux.org.uk> References: <20180402120440.31900-1-liuwenliang@huawei.com> <20180402120440.31900-6-liuwenliang@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-doc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org On Mon, Apr 02, 2018 at 02:08:13PM -0400, Nicolas Pitre wrote: > On Mon, 2 Apr 2018, Abbott Liu wrote: > > > index c79b829..20161e2 100644 > > --- a/arch/arm/kernel/head-common.S > > +++ b/arch/arm/kernel/head-common.S > > @@ -115,6 +115,9 @@ __mmap_switched: > > str r8, [r2] @ Save atags pointer > > cmp r3, #0 > > strne r10, [r3] @ Save control register values > > +#ifdef CONFIG_KASAN > > + bl kasan_early_init > > +#endif > > mov lr, #0 > > b start_kernel > > ENDPROC(__mmap_switched) > > Would be better if lr was cleared before calling kasan_early_init. No. The code is correct - please remember that "bl" writes to LR. The point of clearing LR here is to ensure that start_kernel is called with a zero link register, which it won't be if kasan_early_init is moved after it. -- RMK's Patch system: http://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line in suburbia: sync at 8.8Mbps down 630kbps up According to speedtest.net: 8.21Mbps down 510kbps up -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html