From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-vc0-f181.google.com (mail-vc0-f181.google.com [209.85.220.181]) by kanga.kvack.org (Postfix) with ESMTP id 510956B003A for ; Fri, 26 Sep 2014 13:36:56 -0400 (EDT) Received: by mail-vc0-f181.google.com with SMTP id hq12so3150182vcb.40 for ; Fri, 26 Sep 2014 10:36:54 -0700 (PDT) Received: from mail-vc0-x22f.google.com (mail-vc0-x22f.google.com [2607:f8b0:400c:c03::22f]) by mx.google.com with ESMTPS id ip5si2651829vcb.52.2014.09.26.10.36.54 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Fri, 26 Sep 2014 10:36:54 -0700 (PDT) Received: by mail-vc0-f175.google.com with SMTP id hy4so2221263vcb.34 for ; Fri, 26 Sep 2014 10:36:54 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: References: <1404905415-9046-1-git-send-email-a.ryabinin@samsung.com> <1411562649-28231-1-git-send-email-a.ryabinin@samsung.com> <1411562649-28231-12-git-send-email-a.ryabinin@samsung.com> Date: Fri, 26 Sep 2014 21:36:54 +0400 Message-ID: Subject: Re: [PATCH v3 11/13] kmemleak: disable kasan instrumentation for kmemleak From: Andrey Ryabinin Content-Type: text/plain; charset=UTF-8 Sender: owner-linux-mm@kvack.org List-ID: To: Dmitry Vyukov Cc: Andrey Ryabinin , LKML , Konstantin Serebryany , Dmitry Chernenkov , Andrey Konovalov , Yuri Gribov , Konstantin Khlebnikov , Sasha Levin , Christoph Lameter , Joonsoo Kim , Andrew Morton , Dave Hansen , Andi Kleen , Vegard Nossum , "H. Peter Anvin" , Dave Jones , x86@kernel.org, "linux-mm@kvack.org" , Catalin Marinas 2014-09-26 21:10 GMT+04:00 Dmitry Vyukov : > Looks good to me. > > We can disable kasan instrumentation of this file as well. > Yes, but why? I don't think we need that. > On Wed, Sep 24, 2014 at 5:44 AM, Andrey Ryabinin wrote: >> kmalloc internally round up allocation size, and kmemleak >> uses rounded up size as object's size. This makes kasan >> to complain while kmemleak scans memory or calculates of object's >> checksum. The simplest solution here is to disable kasan. >> >> Signed-off-by: Andrey Ryabinin >> --- >> mm/kmemleak.c | 6 ++++++ >> 1 file changed, 6 insertions(+) >> >> diff --git a/mm/kmemleak.c b/mm/kmemleak.c >> index 3cda50c..9bda1b3 100644 >> --- a/mm/kmemleak.c >> +++ b/mm/kmemleak.c >> @@ -98,6 +98,7 @@ >> #include >> #include >> >> +#include >> #include >> #include >> #include >> @@ -1113,7 +1114,10 @@ static bool update_checksum(struct kmemleak_object *object) >> if (!kmemcheck_is_obj_initialized(object->pointer, object->size)) >> return false; >> >> + kasan_disable_local(); >> object->checksum = crc32(0, (void *)object->pointer, object->size); >> + kasan_enable_local(); >> + >> return object->checksum != old_csum; >> } >> >> @@ -1164,7 +1168,9 @@ static void scan_block(void *_start, void *_end, >> BYTES_PER_POINTER)) >> continue; >> >> + kasan_disable_local(); >> pointer = *ptr; >> + kasan_enable_local(); >> >> object = find_and_get_object(pointer, 1); >> if (!object) >> -- >> 2.1.1 >> > -- Best regards, Andrey Ryabinin -- 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