From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935764AbdJQNED (ORCPT ); Tue, 17 Oct 2017 09:04:03 -0400 Received: from szxga01-in.huawei.com ([45.249.212.187]:14210 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755371AbdJQNEA (ORCPT ); Tue, 17 Oct 2017 09:04:00 -0400 From: "Liuwenliang (Lamb)" To: Ard Biesheuvel CC: kbuild test robot , "kbuild-all@01.org" , "linux@armlinux.org.uk" , "aryabinin@virtuozzo.com" , "afzal.mohd.ma@gmail.com" , "f.fainelli@gmail.com" , "labbott@redhat.com" , "kirill.shutemov@linux.intel.com" , "mhocko@suse.com" , "cdall@linaro.org" , "marc.zyngier@arm.com" , "catalin.marinas@arm.com" , "akpm@linux-foundation.org" , "mawilcox@microsoft.com" , "tglx@linutronix.de" , "thgarnie@google.com" , "keescook@chromium.org" , "arnd@arndb.de" , "vladimir.murzin@arm.com" , "tixy@linaro.org" , "robin.murphy@arm.com" , "mingo@kernel.org" , "grygorii.strashko@linaro.org" , "glider@google.com" , "dvyukov@google.com" , "opendmb@gmail.com" , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "kasan-dev@googlegroups.com" , "linux-mm@kvack.org" , Jiazhenghua , Dailei , Zengweilin , Heshaoliang Subject: Re: [PATCH 04/11] Define the virtual space of KASan's shadow region Thread-Topic: [PATCH 04/11] Define the virtual space of KASan's shadow region Thread-Index: AQHTQmojF4blZnsX90GevfXlGaKSjKLit+AAgAOfd2D//453AIABXTkAgAAu6wCAAJPxEA== Date: Tue, 17 Oct 2017 13:02:06 +0000 Message-ID: References: <20171011082227.20546-5-liuwenliang@huawei.com> <201710141957.mbxeZJHB%fengguang.wu@intel.com> In-Reply-To: Accept-Language: en-US Content-Language: zh-CN X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.57.90.243] Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A090203.59E5FF5E.0004,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0, ip=169.254.12.139, so=2014-11-16 11:51:01, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: 1ea14d3546065720cc58f38fadaf551a Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by nfs id v9HD47Lw020222 On 10/17/2017 8:45 PM, Abbott Liu wrote: >What I said was > >'if the value of TASK_SIZE fits its 12-bit immediate field' > >and your value of TASK_SIZE is 0xb6e00000, which cannot be decomposed in the right way. > >If you build with KASAN disabled, it will generate a mov instruction instead. Thanks for your explain. I understand now. I has tested and the testing result proves that what you said is right. Here is test log: c010e9e0 <__irq_svc>: c010e9e0: e24dd04c sub sp, sp, #76 ; 0x4c c010e9e4: e31d0004 tst sp, #4 c010e9e8: 024dd004 subeq sp, sp, #4 c010e9ec: e88d1ffe stm sp, {r1, r2, r3, r4, r5, r6, r7, r8, r9, sl, fp, ip} c010e9f0: e8900038 ldm r0, {r3, r4, r5} c010e9f4: e28d7030 add r7, sp, #48 ; 0x30 c010e9f8: e3e06000 mvn r6, #0 c010e9fc: e28d204c add r2, sp, #76 ; 0x4c c010ea00: 02822004 addeq r2, r2, #4 c010ea04: e52d3004 push {r3} ; (str r3, [sp, #-4]!) c010ea08: e1a0300e mov r3, lr c010ea0c: e887007c stm r7, {r2, r3, r4, r5, r6} c010ea10: e1a0972d lsr r9, sp, #14 c010ea14: e1a09709 lsl r9, r9, #14 c010ea18: e5990008 ldr r0, [r9, #8] c010ea1c: e3a014bf mov r1, #-1090519040 ; 0xbf000000 // ldr r1,=0xbf000000