From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ed1-f72.google.com (mail-ed1-f72.google.com [209.85.208.72]) by kanga.kvack.org (Postfix) with ESMTP id 4E1B66B02E3 for ; Wed, 31 Oct 2018 06:15:05 -0400 (EDT) Received: by mail-ed1-f72.google.com with SMTP id q10-v6so10406855edd.20 for ; Wed, 31 Oct 2018 03:15:05 -0700 (PDT) Received: from mx1.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id c58-v6si3930133ede.329.2018.10.31.03.15.03 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 31 Oct 2018 03:15:04 -0700 (PDT) Date: Wed, 31 Oct 2018 11:15:01 +0100 From: Michal Hocko Subject: Re: [PATCH v3] mm/page_owner: use kvmalloc instead of kmalloc Message-ID: <20181031101501.GL32673@dhcp22.suse.cz> References: <1540790176-32339-1-git-send-email-miles.chen@mediatek.com> <20181029080708.GA32673@dhcp22.suse.cz> <20181029081706.GC32673@dhcp22.suse.cz> <1540862950.12374.40.camel@mtkswgap22> <20181030060601.GR32673@dhcp22.suse.cz> <1540882551.23278.12.camel@mtkswgap22> <20181030081537.GV32673@dhcp22.suse.cz> <1540975637.10275.10.camel@mtkswgap22> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1540975637.10275.10.camel@mtkswgap22> Sender: owner-linux-mm@kvack.org List-ID: To: Miles Chen Cc: Andrew Morton , Joe Perches , Matthew Wilcox , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, wsd_upstream@mediatek.com On Wed 31-10-18 16:47:17, Miles Chen wrote: > On Tue, 2018-10-30 at 09:15 +0100, Michal Hocko wrote: > > On Tue 30-10-18 14:55:51, Miles Chen wrote: > > [...] > > > It's a real problem when using page_owner. > > > I found this issue recently: I'm not able to read page_owner information > > > during a overnight test. (error: read failed: Out of memory). I replace > > > kmalloc() with vmalloc() and it worked well. > > > > Is this with trimming the allocation to a single page and doing shorter > > than requested reads? > > > I printed out the allocate count on my device the request count is <= > 4096. So I tested this scenario by trimming the count to from 4096 to > 1024 bytes and it works fine. > > count = count > 1024? 1024: count; > > It tested it on both 32bit and 64bit kernel. Are you saying that you see OOMs for 4k size? -- Michal Hocko SUSE Labs