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=-17.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,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 303DDC4167B for ; Thu, 10 Dec 2020 03:26:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EC9502343F for ; Thu, 10 Dec 2020 03:26:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729219AbgLJD0Y (ORCPT ); Wed, 9 Dec 2020 22:26:24 -0500 Received: from mail.kernel.org ([198.145.29.99]:56922 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729542AbgLJD0Q (ORCPT ); Wed, 9 Dec 2020 22:26:16 -0500 Date: Wed, 9 Dec 2020 19:25:35 -0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1607570735; bh=xbEcoW3M2vQ+jrgz4f9vk0ksfGr4mLvgZcEgACBhBgM=; h=From:To:Cc:Subject:Reply-To:References:In-Reply-To:From; b=aWqJ9s2hC652Ab2xsf+4XvRlkctf5Nj4E5uuzxq+r0pyoGTTtT9WwZMWSoRaJSuCf SFeiAko1sWkBkTs+gzNBzeZuK4kbryn+gPucqsFk4GkKjGFJJs/Vvc7dFtAgAKP8lp eP384FK3zmbtFFGvKz97B6scEhLbpwEExiq1p7Vj4mDDDfq1fgWZMaHc1xwCffwqxW 0vdunWXsmZ8Wy1iJWh1TfBf11qvkvxreI8Qmo4gInArrg3S7BJb1I9PVTMVz8FSRdV kJNujMoLN9HPaB/tX1fzXomY/qkHEvTcpazZ4+0dPdGOGYuyifLpnp2b/jkqU4CzHJ CeX8g2gM24/BQ== From: "Paul E. McKenney" To: Vlastimil Babka Cc: rcu@vger.kernel.org, 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 Subject: Re: [PATCH v2 sl-b 2/5] mm: Make mem_dump_obj() handle NULL and zero-sized pointers Message-ID: <20201210032535.GR2657@paulmck-ThinkPad-P72> Reply-To: paulmck@kernel.org References: <20201209011124.GA31164@paulmck-ThinkPad-P72> <20201209011303.32737-2-paulmck@kernel.org> <462f135a-f8e4-6291-6c1c-4fdd2e415462@suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <462f135a-f8e4-6291-6c1c-4fdd2e415462@suse.cz> User-Agent: Mutt/1.9.4 (2018-02-28) Precedence: bulk List-ID: X-Mailing-List: rcu@vger.kernel.org On Wed, Dec 09, 2020 at 06:48:47PM +0100, Vlastimil Babka wrote: > 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 Applied, thank you! Thanx, Paul > > --- > > 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)) { > > >