From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932701AbdC2AZS convert rfc822-to-8bit (ORCPT ); Tue, 28 Mar 2017 20:25:18 -0400 Received: from LGEAMRELO13.lge.com ([156.147.23.53]:52530 "EHLO lgeamrelo13.lge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932352AbdC2AZR (ORCPT ); Tue, 28 Mar 2017 20:25:17 -0400 X-Original-SENDERIP: 156.147.1.127 X-Original-MAILFROM: minchan@kernel.org X-Original-SENDERIP: 165.244.249.26 X-Original-MAILFROM: minchan@kernel.org X-Original-SENDERIP: 10.177.223.161 X-Original-MAILFROM: minchan@kernel.org Date: Wed, 29 Mar 2017 09:20:29 +0900 From: Minchan Kim To: Yisheng Xie CC: , , , Linux Kernel Mailing List , Xishi Qiu , Hanjun Guo Subject: Re: [RFC]mm/zsmalloc,: trigger BUG_ON in function zs_map_object. Message-ID: <20170329002029.GA18979@bbox> References: MIME-Version: 1.0 In-Reply-To: User-Agent: Mutt/1.5.24 (2015-08-30) X-MIMETrack: Itemize by SMTP Server on LGEKRMHUB03/LGE/LG Group(Release 8.5.3FP6|November 21, 2013) at 2017/03/29 09:20:31, Serialize by Router on LGEKRMHUB03/LGE/LG Group(Release 8.5.3FP6|November 21, 2013) at 2017/03/29 09:20:31 Content-Type: text/plain; charset="utf-8" Content-Disposition: inline Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On Tue, Mar 28, 2017 at 03:20:22PM +0800, Yisheng Xie wrote: > Hi, all, > > We had backport the no-lru migration to linux-4.1, meanwhile change the > ZS_MAX_ZSPAGE_ORDER to 3. Then we met a BUG_ON(!page[1]). Hmm, I don't know how you backported. There isn't any problem with default ZS_MAX_ZSPAGE_ORDER. Right? So, it happens only if you changed it to 3? Could you tell me what is your base kernel? and what zram/zsmalloc version(ie, from what kernel version) you backported to your base kernel? > > It rarely happen, and presently, what I get is: > [6823.316528s]obj=a160701f, obj_idx=15, class{size:2176,objs_per_zspage:15,pages_per_zspage:8} > [...] > [6823.316619s]BUG: failure at /home/ethan/kernel/linux-4.1/mm/zsmalloc.c:1458/zs_map_object()! ----> BUG_ON(!page[1]) > > It seems that we have allocated an object from a ZS_FULL group? > (Actually， I do not get the inuse number of this zspage, which I am trying to.) > And presently, I can not find why it happened. Any idea about it? Although it happens rarely, always above same symptom once it happens? > > Any comment is more than welcome! > > Thanks > Yisheng Xie > > > > -- > To unsubscribe, send a message with 'unsubscribe linux-mm' in > the body to majordomo@kvack.org. For more info on Linux MM, > see: http://www.linux-mm.org/ . > Don't email: email@kvack.org