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=-10.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 075A3C433B4 for ; Sat, 3 Apr 2021 01:04:59 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 7AC3E611AC for ; Sat, 3 Apr 2021 01:04:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7AC3E611AC Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 2CF476B0074; Fri, 2 Apr 2021 21:04:57 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 2A86D6B0075; Fri, 2 Apr 2021 21:04:57 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 197A56B0078; Fri, 2 Apr 2021 21:04:57 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0218.hostedemail.com [216.40.44.218]) by kanga.kvack.org (Postfix) with ESMTP id F131A6B0074 for ; Fri, 2 Apr 2021 21:04:56 -0400 (EDT) Received: from smtpin33.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id B57EC8022B13 for ; Sat, 3 Apr 2021 01:04:56 +0000 (UTC) X-FDA: 77989261392.33.52A9153 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf08.hostedemail.com (Postfix) with ESMTP id DDE5380192C0 for ; Sat, 3 Apr 2021 01:04:52 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id C70E16117A; Sat, 3 Apr 2021 01:04:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1617411895; bh=9V7YVCG5U6KqDgGSJ8GVsJXXF4lwYY+bPLYhy58H9qY=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=BmpxYynUul8cO41nW9uTTAZmWIon8i+MoJji+1zno4/f9laEEgkGXcydJUqNaYATo tgs1Kb11/OQX48uN0fpfLws44lwcQCECRqGG7kNZE372kpab+7n3X+yycm50ut2VzA 1eiusBpLTEPoOq6YY49Pvw30UBZPNSlt2SmW0ISM= Date: Fri, 2 Apr 2021 18:04:54 -0700 From: Andrew Morton To: Roman Gushchin Cc: Miaohe Lin , Muchun Song , , , , Christian Borntraeger , , , , Subject: Re: [PATCH] mm: memcontrol: fix forget to obtain the ref to objcg in split_page_memcg Message-Id: <20210402180454.c28395d38396b58659c15fcc@linux-foundation.org> In-Reply-To: References: <20210401030141.37061-1-songmuchun@bytedance.com> <5c183fe6-637f-151c-67f0-fe19a0ce3356@huawei.com> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: DDE5380192C0 X-Stat-Signature: tbkii7nigopcfkzb86qsnearpaj31hok X-Rspamd-Server: rspam02 Received-SPF: none (linux-foundation.org>: No applicable sender policy available) receiver=imf08; identity=mailfrom; envelope-from=""; helo=mail.kernel.org; client-ip=198.145.29.99 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1617411892-169497 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000068, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, 31 Mar 2021 20:35:02 -0700 Roman Gushchin wrote: > On Thu, Apr 01, 2021 at 11:31:16AM +0800, Miaohe Lin wrote: > > On 2021/4/1 11:01, Muchun Song wrote: > > > Christian Borntraeger reported a warning about "percpu ref > > > (obj_cgroup_release) <= 0 (-1) after switching to atomic". > > > Because we forgot to obtain the reference to the objcg and > > > wrongly obtain the reference of memcg. > > > > > > Reported-by: Christian Borntraeger > > > Signed-off-by: Muchun Song > > > > Thanks for the patch. > > Is a Fixes tag needed? > > No, as the original patch hasn't been merged into the Linus's tree yet. > So the fix can be simply squashed. Help. Which is "the original patch"? > Btw, the fix looks good to me. > > Acked-by: Roman Gushchin