Received: by 2002:ac0:a5a6:0:0:0:0:0 with SMTP id m35-v6csp797407imm; Thu, 6 Sep 2018 10:12:40 -0700 (PDT) X-Google-Smtp-Source: ANB0VdbKA0kN1YnHAvRLCzW5V3jz/UyDq9e8n5+GjgXBQfvJHJh8KcN5E+5HnCnsG77DLqtTaHLk X-Received: by 2002:a17:902:e004:: with SMTP id ca4-v6mr3619691plb.252.1536253960605; Thu, 06 Sep 2018 10:12:40 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1536253960; cv=none; d=google.com; s=arc-20160816; b=WgxbUR3hkbVeEKrGpufUvMhNRT2eHbIuKvB/g+Afif6ShTSWo5kdu2eeMv4X4XW8LO 6uv1Asz+H76gwf+l/TwJ7it5Tb/fUJrinpwkurQB6JdztEADEZlMSkRh7EnnP+27kIEZ 8vLTKHQ2H0iswIEo/Sjp6g5OZp2bcmsVY7Evw5NpC9cz+u9MKAF3Tz4ord3l31dsmfD+ VO7QrQfprx/KS0fDPKqIct4wTYjpTzG/0TPWHA99b9EPLW1oAU/v1qkSOvsT4BN0GUuT IAjMsiQxR7bo9f3/+0JEKHkmU847+ytfc/Xywnm4puJh3tDXZTCnPyXNqB3esWSBuhqf aLuw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:user-agent:in-reply-to :content-disposition:mime-version:references:message-id:subject:cc :to:from:date; bh=e8A92bzK5oClQ1c2ZEW18M6TOpcMFu69cXAQbzeirmg=; b=xhybvMXcHJPRgX21RfAp7PTKx2S7Eo4GBGKE7Cr75WxBNAy+XJTL7vrUU9gskupFkb QVgch8y3sZdevwwSP7XnvWHodgRQgeT8OuE9g6cQg+kdq4cumw1f33r1ewqarOx5tXms Y4ebVKqf10DTvUAoTH/P2UqGN3T4WllBtP3KnbagAJd0ow1Jdlz6J1hV1+g2yDVJT/s4 5ADDdM8dcdxJU8ejsYSpB6w75bJuJ7Ibghfhljhpl3KznLIIsiyPtdzRTLZFMGdeCvwV 77/8xBkOxDMasL9Q8iKfkENN2b0brZrL+iNrt+mzxtvNXPHc51Jip60aCvEPUmZX8IIQ rXDw== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id e7-v6si5662370pge.42.2018.09.06.10.12.23; Thu, 06 Sep 2018 10:12:40 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728952AbeIFVok (ORCPT + 99 others); Thu, 6 Sep 2018 17:44:40 -0400 Received: from mx2.suse.de ([195.135.220.15]:53360 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728603AbeIFVok (ORCPT ); Thu, 6 Sep 2018 17:44:40 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 04E32AEF2; Thu, 6 Sep 2018 17:08:14 +0000 (UTC) Date: Thu, 6 Sep 2018 19:08:13 +0200 From: Michal Hocko To: Dave Hansen Cc: Alexander Duyck , linux-mm@kvack.org, linux-kernel@vger.kernel.org, alexander.h.duyck@intel.com, pavel.tatashin@microsoft.com, akpm@linux-foundation.org, mingo@kernel.org, kirill.shutemov@linux.intel.com Subject: Re: [PATCH v2 1/2] mm: Move page struct poisoning to CONFIG_DEBUG_VM_PAGE_INIT_POISON Message-ID: <20180906170813.GF14951@dhcp22.suse.cz> References: <20180905211041.3286.19083.stgit@localhost.localdomain> <20180905211328.3286.71674.stgit@localhost.localdomain> <20180906054735.GJ14951@dhcp22.suse.cz> <0c1c36f7-f45a-8fe9-dd52-0f60b42064a9@intel.com> <20180906151336.GD14951@dhcp22.suse.cz> <33f39b37-9567-88a8-097d-a63df04c7732@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <33f39b37-9567-88a8-097d-a63df04c7732@intel.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu 06-09-18 09:09:46, Dave Hansen wrote: [...] > Has anyone ever seen a single in-the-wild report from this mechanism? Yes. See the list from Pavel. And I wouldn't push for it otherwise. There are some questionable asserts with an overhead which is not directly visible but it just adds up. This is different that it is one time boot rare thing. Anyway, I guess I have put all my arguments on the table. I will leave the decision to you guys. If there is a strong concensus about a config option, then I can live with that and will enable it. -- Michal Hocko SUSE Labs