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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 CE976C33CB6 for ; Fri, 17 Jan 2020 15:47:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A4AD62083E for ; Fri, 17 Jan 2020 15:47:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579276022; bh=FCadZVbrTnJdhC2tSCPz5DKRVsjw4WKCW2LDnjxNG/U=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=r1YUPcwwwkr6QSL2zHYI9y1WyNiToXngp5rpfXwimORGBY61XQ8T0ERcEVgHMwv8M q7ZomdzM6DzPq1QKSxq4sXOUymmeY1aCQH52xQDb/4NtSYEql8lWdS6S23QR+D+P3e S8fr1GJqQb+/EN/m6QgyiuRBe3v41YZ8L6e5icdY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729188AbgAQPrB (ORCPT ); Fri, 17 Jan 2020 10:47:01 -0500 Received: from mail-wm1-f68.google.com ([209.85.128.68]:53026 "EHLO mail-wm1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728816AbgAQPrB (ORCPT ); Fri, 17 Jan 2020 10:47:01 -0500 Received: by mail-wm1-f68.google.com with SMTP id p9so7916555wmc.2 for ; Fri, 17 Jan 2020 07:46:59 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=3Bj0wpfeG4WUbynTokfuhSk08I/UsNl1uvGCOq3jYT0=; b=tzZRYC8OABVTP1W0y3Dim9rK+94HNd9Sw/aRkd6WTEwx4ae9Upw7FtE9ki9m6YQeUS UKpyXwudhvbhiKC1t2Q7ctyLIrPGs292gUUrQDXPxkK3HrHzUVGoSqsM7ArHlT9GNHGe B7+VQmhNzXqwY00sw5CSDfHdD0ns5JkavVh/GwMGoFu12rNpF+2Q2bns0sBPy9fpPN2X AvniLcTQ7gw1v8LEVwIKi8LqtIheFLwonAe8Um8/5Wp/rxPp0TcMarqheGDjlD/bFy4N jSFsbPEtmpm6ThEXqXactlCZiG+TNS6rc9i7e1QMe7Du62WESREdXb6BW7GvIWqx9WWt 4slg== X-Gm-Message-State: APjAAAWCk+F1RkePcrPhRzvQfB3y40B86uXPLdU2uPOiWcYOvkhYy3uf cuqqYUt9p4uq1SztuX1a+L4= X-Google-Smtp-Source: APXvYqxvFy2I3vgmVlD3PjVc6nrcUsOWbf3nQbihKUYrVjXoA2ms3aHznTtU5u1TdPGXx8upDvD4lg== X-Received: by 2002:a1c:f218:: with SMTP id s24mr5462989wmc.128.1579276019240; Fri, 17 Jan 2020 07:46:59 -0800 (PST) Received: from localhost (prg-ext-pat.suse.com. [213.151.95.130]) by smtp.gmail.com with ESMTPSA id s128sm10370683wme.39.2020.01.17.07.46.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 17 Jan 2020 07:46:58 -0800 (PST) Date: Fri, 17 Jan 2020 16:46:57 +0100 From: Michal Hocko To: Qian Cai Cc: akpm@linux-foundation.org, sergey.senozhatsky.work@gmail.com, pmladek@suse.com, rostedt@goodmis.org, peterz@infradead.org, david@redhat.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH -next v4] mm/hotplug: silence a lockdep splat with printk() Message-ID: <20200117154657.GL19428@dhcp22.suse.cz> References: <20200117143905.GZ19428@dhcp22.suse.cz> <3B7490FB-E915-4DC7-8739-01EDC023E22E@lca.pw> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <3B7490FB-E915-4DC7-8739-01EDC023E22E@lca.pw> User-Agent: Mutt/1.12.2 (2019-09-21) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri 17-01-20 10:05:12, Qian Cai wrote: > > > > On Jan 17, 2020, at 9:39 AM, Michal Hocko wrote: > > > > Thanks a lot. Having it in a separate patch would be great. > > I was thinking about removing that WARN together in this v5 patch, > so there is less churn to touch the same function again. However, I > am fine either way, so just shout out if you feel strongly towards a > separate patch. I hope you meant moving rather than removing ;). The warning is useful because we shouldn't see unmovable pages in the movable zone. And a separate patch makes more sense because the justification is slightly different. We do not want to have a way for userspace to trigger the warning from userspace - even though it shouldn't be possible, but still. Only the offlining path should complain. -- Michal Hocko SUSE Labs