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=-2.5 required=3.0 tests=MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 AE86FC10F14 for ; Tue, 8 Oct 2019 13:48:35 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 65531206BB for ; Tue, 8 Oct 2019 13:48:35 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 65531206BB Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id D2D9D8E0005; Tue, 8 Oct 2019 09:48:34 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id CDE1E8E0003; Tue, 8 Oct 2019 09:48:34 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id BF43E8E0005; Tue, 8 Oct 2019 09:48:34 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0117.hostedemail.com [216.40.44.117]) by kanga.kvack.org (Postfix) with ESMTP id 9DDA48E0003 for ; Tue, 8 Oct 2019 09:48:34 -0400 (EDT) Received: from smtpin12.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with SMTP id 5020F181AC9B4 for ; Tue, 8 Oct 2019 13:48:34 +0000 (UTC) X-FDA: 76020747348.12.fall29_4ac93225e735f X-HE-Tag: fall29_4ac93225e735f X-Filterd-Recvd-Size: 2105 Received: from mx1.suse.de (mx2.suse.de [195.135.220.15]) by imf42.hostedemail.com (Postfix) with ESMTP for ; Tue, 8 Oct 2019 13:48:33 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 13FFBB1AC; Tue, 8 Oct 2019 13:48:32 +0000 (UTC) Date: Tue, 8 Oct 2019 15:48:31 +0200 From: Michal Hocko To: Petr Mladek Cc: Qian Cai , Steven Rostedt , sergey.senozhatsky.work@gmail.com, peterz@infradead.org, linux-mm@kvack.org, john.ogness@linutronix.de, akpm@linux-foundation.org, david@redhat.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] mm/page_isolation: fix a deadlock with printk() Message-ID: <20191008134831.GL6681@dhcp22.suse.cz> References: <1570228005-24979-1-git-send-email-cai@lca.pw> <20191007143002.l37bt2lzqtnqjqxu@pathway.suse.cz> <1570460350.5576.290.camel@lca.pw> <20191007151237.GP2381@dhcp22.suse.cz> <1570462407.5576.292.camel@lca.pw> <20191008081510.ptwmb7zflqiup5py@pathway.suse.cz> <20191008091349.6195830d@gandalf.local.home> <1570541032.5576.297.camel@lca.pw> <20191008134256.5ti6rjkvadn5b5q4@pathway.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191008134256.5ti6rjkvadn5b5q4@pathway.suse.cz> User-Agent: Mutt/1.10.1 (2018-07-13) 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 Tue 08-10-19 15:42:56, Petr Mladek wrote: [...] > I am not -mm maintainer so I could not guarantee that a patch > using printk_deferred() will get accepted. But it will have much > bigger chance than the original patch. I am not going to ack any such patch until it is clear what is the actual problem. The disucssion in this thread boils down to point to lockdep splats which are most likely false possitives and there is no clear evidence that the is any actual deadlock as those would be clearly identifiable if the zone->lock or any other spinlock spinlock were participating. -- Michal Hocko SUSE Labs