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=-7.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 12650C432BE for ; Fri, 23 Jul 2021 07:02:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EB8F960EAF for ; Fri, 23 Jul 2021 07:02:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234212AbhGWGVf (ORCPT ); Fri, 23 Jul 2021 02:21:35 -0400 Received: from mail.kernel.org ([198.145.29.99]:57978 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234089AbhGWGVe (ORCPT ); Fri, 23 Jul 2021 02:21:34 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id F252A60EE2; Fri, 23 Jul 2021 07:02:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1627023728; bh=02LUfP9gRBAKznttDT6gEA8Wm5l4jpvhTQOhmSmp6TY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=oYElD2rhN77kwhk3cHbdJs1c1K4EEL9wI8fe4Uw3mOaPEtxJSMnhDjUPbEEf1SAzA YEHykz6fGqLgjZZ4asnYJ3GIswCFOu2g/Z98w+hF9lyqReoghUDstiJGuK44r8OyR6 EhDzQXwJgbKvoHxsJjXUSHkuXAx5ulAcvQyMelNA= Date: Fri, 23 Jul 2021 09:02:05 +0200 From: Greg KH To: Miaohe Lin Cc: Matthew Wilcox , Zhouyi Zhou , Chris Clayton , Oleksandr Natalenko , Boqun Feng , paulmck@kernel.org, linux-kernel , stable@vger.kernel.org, Chris Rankin , Josh Triplett , Steven Rostedt , Mathieu Desnoyers , Lai Jiangshan , Joel Fernandes , rcu , Andrew Morton , Linux-MM , "Huang, Ying" Subject: Re: linux-5.13.2: warning from kernel/rcu/tree_plugin.h:359 Message-ID: References: <2237123.PRLUojbHBq@natalenko.name> <01fef2db-bd7e-12b6-ec21-2addd02e7062@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <01fef2db-bd7e-12b6-ec21-2addd02e7062@huawei.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jul 23, 2021 at 09:51:09AM +0800, Miaohe Lin wrote: > On 2021/7/22 22:00, Greg KH wrote: > > On Thu, Jul 22, 2021 at 03:26:52PM +0200, Greg KH wrote: > >> On Thu, Jul 22, 2021 at 01:36:02PM +0100, Matthew Wilcox wrote: > >>> On Thu, Jul 22, 2021 at 04:57:57PM +0800, Zhouyi Zhou wrote: > >>>> Thanks for reviewing, > >>>> > >>>> What I have deduced from the dmesg is: > >>>> In function do_swap_page, > >>>> after invoking > >>>> 3385 si = get_swap_device(entry); /* rcu_read_lock */ > >>>> and before > >>>> 3561 out: > >>>> 3562 if (si) > >>>> 3563 put_swap_device(si); > >>>> The thread got scheduled out in > >>>> 3454 locked = lock_page_or_retry(page, vma->vm_mm, vmf->flags); > >>>> > >>>> I am only familiar with Linux RCU subsystem, hope mm people can solve our > >>>> confusions. > >>> > >>> I don't understamd why you're still talking. The problem is understood. > >>> You need to revert the unnecessary backport of 2799e77529c2 and > >>> 2efa33fc7f6e > >> > >> Sorry for the delay, will go do so in a minute... > > > > Both now reverted from 5.10.y and 5.13.y. > > > > I browsed my previous backport notifying email and found that these two patches are also > backported into 5.12. And it seems it's missed. 5.12 is now end-of-life, it's not being touched anymore, and no one should continue to use it. thanks, greg k-h