From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 01CA6C4361B for ; Wed, 9 Dec 2020 17:48:53 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 85B8A225AA for ; Wed, 9 Dec 2020 17:48:52 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 85B8A225AA Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.cz Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id D2F8B6B009E; Wed, 9 Dec 2020 12:48:51 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id CB8EF6B009F; Wed, 9 Dec 2020 12:48:51 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B80556B00A1; Wed, 9 Dec 2020 12:48:51 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0205.hostedemail.com [216.40.44.205]) by kanga.kvack.org (Postfix) with ESMTP id 9DDB96B009E for ; Wed, 9 Dec 2020 12:48:51 -0500 (EST) Received: from smtpin06.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 6652C824999B for ; Wed, 9 Dec 2020 17:48:51 +0000 (UTC) X-FDA: 77574479262.06.ants69_5e07fbc273f1 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin06.hostedemail.com (Postfix) with ESMTP id 1A8431004D260 for ; Wed, 9 Dec 2020 17:48:51 +0000 (UTC) X-HE-Tag: ants69_5e07fbc273f1 X-Filterd-Recvd-Size: 2872 Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by imf30.hostedemail.com (Postfix) with ESMTP for ; Wed, 9 Dec 2020 17:48:50 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 09C7EAD0E; Wed, 9 Dec 2020 17:48:49 +0000 (UTC) Subject: Re: [PATCH v2 sl-b 2/5] mm: Make mem_dump_obj() handle NULL and zero-sized pointers To: paulmck@kernel.org, rcu@vger.kernel.org Cc: linux-kernel@vger.kernel.org, kernel-team@fb.com, mingo@kernel.org, jiangshanlai@gmail.com, akpm@linux-foundation.org, mathieu.desnoyers@efficios.com, josh@joshtriplett.org, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com, fweisbec@gmail.com, oleg@redhat.com, joel@joelfernandes.org, iamjoonsoo.kim@lge.com, andrii@kernel.org, Christoph Lameter , Pekka Enberg , David Rientjes , linux-mm@kvack.org References: <20201209011124.GA31164@paulmck-ThinkPad-P72> <20201209011303.32737-2-paulmck@kernel.org> From: Vlastimil Babka Message-ID: <462f135a-f8e4-6291-6c1c-4fdd2e415462@suse.cz> Date: Wed, 9 Dec 2020 18:48:47 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.5.1 MIME-Version: 1.0 In-Reply-To: <20201209011303.32737-2-paulmck@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 12/9/20 2:13 AM, paulmck@kernel.org wrote: > From: "Paul E. McKenney" > > This commit makes mem_dump_obj() call out NULL and zero-sized pointers > specially instead of classifying them as non-paged memory. > > Cc: Christoph Lameter > Cc: Pekka Enberg > Cc: David Rientjes > Cc: Joonsoo Kim > Cc: Andrew Morton > Cc: > Reported-by: Andrii Nakryiko > Signed-off-by: Paul E. McKenney Acked-by: Vlastimil Babka > --- > mm/util.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/mm/util.c b/mm/util.c > index d0e60d2..8c2449f 100644 > --- a/mm/util.c > +++ b/mm/util.c > @@ -985,7 +985,12 @@ int __weak memcmp_pages(struct page *page1, struct page *page2) > void mem_dump_obj(void *object) > { > if (!virt_addr_valid(object)) { > - pr_cont(" non-paged (local) memory.\n"); > + if (object == NULL) > + pr_cont(" NULL pointer.\n"); > + else if (object == ZERO_SIZE_PTR) > + pr_cont(" zero-size pointer.\n"); > + else > + pr_cont(" non-paged (local) memory.\n"); > return; > } > if (kmem_valid_obj(object)) { >