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=-2.1 required=3.0 tests=DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,T_DKIM_INVALID, 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 90949C28CF6 for ; Wed, 25 Jul 2018 01:55:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3E4E520856 for ; Wed, 25 Jul 2018 01:55:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="OtiTPZrY" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3E4E520856 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org 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 S1728210AbeGYDEW (ORCPT ); Tue, 24 Jul 2018 23:04:22 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:34616 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727353AbeGYDEW (ORCPT ); Tue, 24 Jul 2018 23:04:22 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=vseEyQ7B7P/dMO97ZbxiAJRke0PaTr9mg/p2ASQFsAc=; b=OtiTPZrYpSmBiFtEZtbPRmrhy 6wEfGfSsjct3BPEpUyesZGk5NVo0vHS7lIIjW7I6RpFt/LWeVylx+I4UC+20p+3880jdDILwpXHNQ uaqLBfAW/Xl6/GhTD0Rl9cJLv8/ab1mgnOXE1yJm/BgDIwt6c1Sx28OzGsrZ96MjW+HpMSXFyqz6q cdusNDFeZQWsoMLX3AZLwbp113K5tHvJZ5lhh6J+lgp1qNWGS5LzrdK8EYS3q6C5db1KThYUyKGJk uzotbOfzIQmI/gb2uTakMnOinYV0ouCnPrUkh/UpxEHPE3hVP+dmH/IOXKiRC8SGMF+I6I9ZL47Sl RKvtij+vg==; Received: from willy by bombadil.infradead.org with local (Exim 4.90_1 #2 (Red Hat Linux)) id 1fi914-00062R-IM; Wed, 25 Jul 2018 01:55:02 +0000 Date: Tue, 24 Jul 2018 18:55:02 -0700 From: Matthew Wilcox To: Minchan Kim Cc: Tino Lehnig , ngupta@vflare.org, linux-kernel@vger.kernel.org, Sergey Senozhatsky , Andrew Morton Subject: Re: Zram writeback feature unstable with heavy swap utilization - BUG: Bad page state in process... Message-ID: <20180725015502.GA16271@bombadil.infradead.org> References: <0516ae2d-b0fd-92c5-aa92-112ba7bd32fc@contabo.de> <20180724010342.GA195675@rodete-desktop-imager.corp.google.com> <20180725013250.GA66792@rodete-desktop-imager.corp.google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180725013250.GA66792@rodete-desktop-imager.corp.google.com> User-Agent: Mutt/1.9.2 (2017-12-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jul 25, 2018 at 10:32:50AM +0900, Minchan Kim wrote: > Hi Tino, > > On Tue, Jul 24, 2018 at 09:30:34AM +0200, Tino Lehnig wrote: > > Hi, > > > > The first build I used was from the master branch of the mainline kernel, > > somewhere between rc5 and rc6. I have just reproduced the bug with 4.17.9 > > and 4.18-rc6. Kernel messages below. > > > > The bug does not appear on 4.14.57. I can test more versions if it helps. > > Could you try 4.15? > > I think it's a regression of struct page field reordring and it started from > v4.16. > > page->units for zsmalloc is used as offset of first object on the zspage, > However, below patch unified it with page->_refcount. No it didn't. It's in a union with _mapcount, which is where it was before my patches. It's entiely possible that my patches caused this, but the explanation you're offering is wrong.