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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,UNPARSEABLE_RELAY 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 3D980C0044C for ; Wed, 31 Oct 2018 10:20:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EA72220685 for ; Wed, 31 Oct 2018 10:19:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EA72220685 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=mediatek.com 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 S1728267AbeJaTR1 (ORCPT ); Wed, 31 Oct 2018 15:17:27 -0400 Received: from mailgw01.mediatek.com ([210.61.82.183]:2310 "EHLO mailgw01.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1727852AbeJaTR1 (ORCPT ); Wed, 31 Oct 2018 15:17:27 -0400 X-UUID: a01d6aa4ff4e453aa6a678f0eac8928f-20181031 X-UUID: a01d6aa4ff4e453aa6a678f0eac8928f-20181031 Received: from mtkcas08.mediatek.inc [(172.21.101.126)] by mailgw01.mediatek.com (envelope-from ) (mhqrelay.mediatek.com ESMTP with TLS) with ESMTP id 1806330942; Wed, 31 Oct 2018 18:19:43 +0800 Received: from MTKCAS06.mediatek.inc (172.21.101.30) by mtkmbs03n2.mediatek.inc (172.21.101.182) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Wed, 31 Oct 2018 18:19:42 +0800 Received: from [172.21.77.33] (172.21.77.33) by MTKCAS06.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1395.4 via Frontend Transport; Wed, 31 Oct 2018 18:19:42 +0800 Message-ID: <1540981182.16084.1.camel@mtkswgap22> Subject: Re: [PATCH v3] mm/page_owner: use kvmalloc instead of kmalloc From: Miles Chen To: Michal Hocko CC: Andrew Morton , Joe Perches , Matthew Wilcox , , , , , Date: Wed, 31 Oct 2018 18:19:42 +0800 In-Reply-To: <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> <20181031101501.GL32673@dhcp22.suse.cz> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3-0ubuntu6 Content-Transfer-Encoding: 7bit MIME-Version: 1.0 X-TM-SNTS-SMTP: 31A53AD034CBF0DCA792824C567B80F5D0BDF81AFCA42A2E2F46CE800FDA46072000:8 X-MTK: N Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2018-10-31 at 11:15 +0100, Michal Hocko wrote: > 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? > yes, because kmalloc only use normal memor, not highmem + normal memory I think that's why vmalloc() works.