From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AIpwx4/jbVcqFHd4O0xcf9vRBYnVOUJRuz1OM9BCdEXA5+bqI625vCypVxlXmDLR9HvGeFjgE0Yb ARC-Seal: i=1; a=rsa-sha256; t=1522692990; cv=none; d=google.com; s=arc-20160816; b=XE0yfysR9A63zSJozAZ0rRgdjJ9MT5yZCpCAV6h0Yeo5InI1/NEDW9eUbJbKGeicro hj/u/9F29MUAzto684/g6NKyAsioDd3yy8s49bF0itqJnyDdiUwPirnK33wVf5Z/BWMy oz61ngbW9JsrPZ03G6fWe6/bRgpyUpdccMYGlRNFtSzF9aLFyVIdYptgVqdlhc7jA7hA ENSpYcqm4LGC1i1KuXsA2kc1pVDpE3p/a/7GGltWHv8Vmv6A5vQ+kbmmuG7+V1WNmYox f8hqvkZEC/2po3WPdZe/6firaSDSEew3tlEovi6VY+Psd8THTUFSPExIWDY9UNAyUrYy s7Lg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=sender:user-agent:in-reply-to:content-disposition:mime-version :references:message-id:subject:cc:to:from:date:dkim-signature :arc-authentication-results; bh=jYfSrkpv8FOUzemlQoG3h7Mxq7My+IRLeJola3h8FBw=; b=JZWgmqm4hCskgErOpNqeJVP6YASHucbueDUHea0oH8yjGxgmfxNcSU401Xb1Bcb9xw LVzX0Yp/mi4Nmi2ZueoqlZxTqv6Vd3Rf6xmruEesW+uAxS/dRoQKFe6eBUQjhbxFpBTU pfWKis8W/G6PenoT3ss00732lQWpTfq2b9OYJJK9GXPEsjZjvThN0kpQiNdhydOAO6ZK xHha3FPCLNJ7JBJPRZ8D8IM5Dbb5iA/Okw8Lpi3IT1oNnLFwRt6ku+eascMH6lJ6bTOS ktwmhFtlZKS/JLQol+ykdbHhZisYcMPFy5Cze5fltHwiVy/P3DiNLjm+EaC5F6t9zIGO GMdQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@armlinux.org.uk header.s=pandora-2014 header.b=rPxSnY+D; spf=pass (google.com: best guess record for domain of linux+gregkh=linuxfoundation.org@armlinux.org.uk designates 2001:4d48:ad52:3201:214:fdff:fe10:1be6 as permitted sender) smtp.mailfrom=linux+gregkh=linuxfoundation.org@armlinux.org.uk; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=armlinux.org.uk Authentication-Results: mx.google.com; dkim=pass header.i=@armlinux.org.uk header.s=pandora-2014 header.b=rPxSnY+D; spf=pass (google.com: best guess record for domain of linux+gregkh=linuxfoundation.org@armlinux.org.uk designates 2001:4d48:ad52:3201:214:fdff:fe10:1be6 as permitted sender) smtp.mailfrom=linux+gregkh=linuxfoundation.org@armlinux.org.uk; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=armlinux.org.uk 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: Russell King - ARM Linux X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1596637214651692602?= X-GMAIL-MSGID: =?utf-8?q?1596659325367854757?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 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