From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-it0-f71.google.com (mail-it0-f71.google.com [209.85.214.71]) by kanga.kvack.org (Postfix) with ESMTP id 6CDB56B038E for ; Mon, 6 Mar 2017 11:11:35 -0500 (EST) Received: by mail-it0-f71.google.com with SMTP id r141so80364566ita.6 for ; Mon, 06 Mar 2017 08:11:35 -0800 (PST) Received: from EUR01-VE1-obe.outbound.protection.outlook.com (mail-ve1eur01on0118.outbound.protection.outlook.com. [104.47.1.118]) by mx.google.com with ESMTPS id 125si11261313ite.70.2017.03.06.08.11.33 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 06 Mar 2017 08:11:34 -0800 (PST) Subject: Re: [PATCH v2 6/9] kasan: improve slab object description References: <20170302134851.101218-1-andreyknvl@google.com> <20170302134851.101218-7-andreyknvl@google.com> <2bbe7bdc-8842-8ec0-4b5a-6a8dce39216d@virtuozzo.com> From: Andrey Ryabinin Message-ID: <576aeb81-9408-13fa-041d-a6bd1e2cf895@virtuozzo.com> Date: Mon, 6 Mar 2017 19:12:41 +0300 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Andrey Konovalov Cc: Alexander Potapenko , Dmitry Vyukov , kasan-dev , Linux Memory Management List , LKML On 03/06/2017 04:45 PM, Andrey Konovalov wrote: > On Fri, Mar 3, 2017 at 3:39 PM, Andrey Ryabinin wrote: >> >> >> On 03/03/2017 04:52 PM, Alexander Potapenko wrote: >>> On Fri, Mar 3, 2017 at 2:31 PM, Andrey Ryabinin wrote: >>>> On 03/02/2017 04:48 PM, Andrey Konovalov wrote: >>>>> Changes slab object description from: >>>>> >>>>> Object at ffff880068388540, in cache kmalloc-128 size: 128 >>>>> >>>>> to: >>>>> >>>>> The buggy address belongs to the object at ffff880068388540 >>>>> which belongs to the cache kmalloc-128 of size 128 >>>>> The buggy address is located 123 bytes inside of >>>>> 128-byte region [ffff880068388540, ffff8800683885c0) >>>>> >>>>> Makes it more explanatory and adds information about relative offset >>>>> of the accessed address to the start of the object. >>>>> >>>> >>>> I don't think that this is an improvement. You replaced one simple line with a huge >>>> and hard to parse text without giving any new/useful information. >>>> Except maybe offset, it useful sometimes, so wouldn't mind adding it to description. >>> Agreed. >>> How about: >>> =========== >>> Access 123 bytes inside of 128-byte region [ffff880068388540, ffff8800683885c0) >>> Object at ffff880068388540 belongs to the cache kmalloc-128 >>> =========== >>> ? >>> >> >> I would just add the offset in the end: >> Object at ffff880068388540, in cache kmalloc-128 size: 128 accessed at offset y > > Access can be inside or outside the object, so it's better to > specifically say that. > That what access offset and object's size tells us. > I think we can do (basically what Alexander suggested): > > Object at ffff880068388540 belongs to the cache kmalloc-128 of size 128 > Access 123 bytes inside of 128-byte region [ffff880068388540, ffff8800683885c0) This is just wrong and therefore very confusing. The message says that we access 123 bytes, while in fact we access x-bytes at offset 123. IOW 123 sounds like access size here not the offset. > What do you think? > Not better. -- 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