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=-2.4 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT 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 C0197C07E85 for ; Tue, 11 Dec 2018 16:39:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 883FD20855 for ; Tue, 11 Dec 2018 16:39:56 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 883FD20855 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.cz Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727583AbeLKQjz (ORCPT ); Tue, 11 Dec 2018 11:39:55 -0500 Received: from mx2.suse.de ([195.135.220.15]:46540 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726851AbeLKQjy (ORCPT ); Tue, 11 Dec 2018 11:39:54 -0500 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 07BBEAF89; Tue, 11 Dec 2018 16:39:53 +0000 (UTC) Received: by quack2.suse.cz (Postfix, from userid 1000) id 0D0F91E13F8; Tue, 11 Dec 2018 17:39:52 +0100 (CET) Date: Tue, 11 Dec 2018 17:39:52 +0100 From: Jan Kara To: Michal Hocko Cc: "Kirill A. Shutemov" , Andrew Morton , Liu Bo , Jan Kara , Dave Chinner , Theodore Ts'o , Johannes Weiner , Vladimir Davydov , linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, LKML Subject: Re: [PATCH] mm, memcg: fix reclaim deadlock with writeback Message-ID: <20181211163952.GB4020@quack2.suse.cz> References: <20181211132645.31053-1-mhocko@kernel.org> <20181211151542.2rjti4glj75honje@kshutemo-mobl1> <20181211162149.GL1286@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181211162149.GL1286@dhcp22.suse.cz> 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 Tue 11-12-18 17:21:49, Michal Hocko wrote: > On Tue 11-12-18 18:15:42, Kirill A. Shutemov wrote: > > For instance, DAX page fault will setup page table entry on its own and > > return VM_FAULT_NOPAGE. It uses vmf_insert_mixed() to setup the page table > > and ignores your pre-allocated page table. > > Does this happen with a page locked and with __GFP_ACCOUNT allocation. I > am not familiar with that code but I do not see it from a quick look. DAX has no page to lock and also no writeback to do so the deadlock isn't really possible when DAX is in use... Honza -- Jan Kara SUSE Labs, CR