From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr0-f197.google.com (mail-wr0-f197.google.com [209.85.128.197]) by kanga.kvack.org (Postfix) with ESMTP id 4AA686B0069 for ; Thu, 19 Oct 2017 08:42:06 -0400 (EDT) Received: by mail-wr0-f197.google.com with SMTP id n4so3981510wrb.8 for ; Thu, 19 Oct 2017 05:42:06 -0700 (PDT) Received: from pandora.armlinux.org.uk (pandora.armlinux.org.uk. [2001:4d48:ad52:3201:214:fdff:fe10:1be6]) by mx.google.com with ESMTPS id w6si1484285wra.4.2017.10.19.05.42.04 for (version=TLS1 cipher=AES128-SHA bits=128/128); Thu, 19 Oct 2017 05:42:05 -0700 (PDT) Date: Thu, 19 Oct 2017 13:41:49 +0100 From: Russell King - ARM Linux Subject: Re: [PATCH 04/11] Define the virtual space of KASan's shadow region Message-ID: <20171019124149.GX20805@n2100.armlinux.org.uk> References: <20171011082227.20546-5-liuwenliang@huawei.com> <201710141957.mbxeZJHB%fengguang.wu@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: Ard Biesheuvel Cc: "Liuwenliang (Lamb)" , "tixy@linaro.org" , "mhocko@suse.com" , "grygorii.strashko@linaro.org" , "catalin.marinas@arm.com" , "linux-mm@kvack.org" , "glider@google.com" , "afzal.mohd.ma@gmail.com" , "mingo@kernel.org" , "cdall@linaro.org" , "f.fainelli@gmail.com" , kbuild test robot , "mawilcox@microsoft.com" , "kasan-dev@googlegroups.com" , Dailei , "linux-arm-kernel@lists.infradead.org" , "aryabinin@virtuozzo.com" , "labbott@redhat.com" , "vladimir.murzin@arm.com" , "keescook@chromium.org" , "arnd@arndb.de" , "marc.zyngier@arm.com" , Zengweilin , "opendmb@gmail.com" , Heshaoliang , "tglx@linutronix.de" , "dvyukov@google.com" , "linux-kernel@vger.kernel.org" , "kbuild-all@01.org" , Jiazhenghua , "akpm@linux-foundation.org" , "robin.murphy@arm.com" , "thgarnie@google.com" , "kirill.shutemov@linux.intel.com" On Mon, Oct 16, 2017 at 01:14:54PM +0100, Ard Biesheuvel wrote: > On 16 October 2017 at 12:42, Liuwenliang (Lamb) wrote: > > On 10/16/2017 07:03 PM, Abbott Liu wrote: > >>arch/arm/kernel/entry-armv.S:348: Error: selected processor does not support `movw r1, > > #:lower16:((((0xC0000000-0x01000000)>>3)+((0xC0000000-0x01000000)-(1<<29))))' in ARM mode > >>arch/arm/kernel/entry-armv.S:348: Error: selected processor does not support `movt r1, > > #:upper16:((((0xC0000000-0x01000000)>>3)+((0xC0000000-0x01000000)-(1<<29))))' in ARM mode > > > > Thanks for building test. This error can be solved by following code: > > --- a/arch/arm/kernel/entry-armv.S > > +++ b/arch/arm/kernel/entry-armv.S > > @@ -188,8 +188,7 @@ ENDPROC(__und_invalid) > > get_thread_info tsk > > ldr r0, [tsk, #TI_ADDR_LIMIT] > > #ifdef CONFIG_KASAN > > - movw r1, #:lower16:TASK_SIZE > > - movt r1, #:upper16:TASK_SIZE > > + ldr r1, =TASK_SIZE > > #else > > mov r1, #TASK_SIZE > > #endif > > This is unnecessary: > > ldr r1, =TASK_SIZE > > will be converted to a mov instruction by the assembler if the value > of TASK_SIZE fits its 12-bit immediate field. It's an 8-bit immediate field for ARM. What it won't do is expand it to a pair of movw/movt instructions if it doesn't fit. -- 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, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org