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=-10.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 36F65C433E0 for ; Fri, 12 Mar 2021 06:31:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 05EE464F76 for ; Fri, 12 Mar 2021 06:31:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231613AbhCLGaz (ORCPT ); Fri, 12 Mar 2021 01:30:55 -0500 Received: from mga18.intel.com ([134.134.136.126]:45510 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231544AbhCLGai (ORCPT ); Fri, 12 Mar 2021 01:30:38 -0500 IronPort-SDR: ZMpMqxuXhYPozrrWPTuLRmpSG2sSNpUrEHSanUIPw3t4Sk0eGjx8O8Q/c7YjAgXHy39pu/2Jdw 6/sC21qterLw== X-IronPort-AV: E=McAfee;i="6000,8403,9920"; a="176381654" X-IronPort-AV: E=Sophos;i="5.81,242,1610438400"; d="scan'208";a="176381654" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Mar 2021 22:30:37 -0800 IronPort-SDR: Co3t1pgsRLHMkBiBltp/iyMwsnvZq+XrKmqVVH6NmbGcSkmcNfcKn1KISXa8+2D8dUMfYMWCRp yfFFdTIv10Jw== X-IronPort-AV: E=Sophos;i="5.81,242,1610438400"; d="scan'208";a="410904374" Received: from xsang-optiplex-9020.sh.intel.com (HELO xsang-OptiPlex-9020) ([10.239.159.140]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Mar 2021 22:30:34 -0800 Date: Fri, 12 Mar 2021 14:27:55 +0800 From: Oliver Sang To: Ira Weiny Cc: Chaitanya Kulkarni , David Sterba , Andrew Morton , "hch@infradead.org" , Christoph Hellwig , LKML , "lkp@lists.01.org" , "lkp@intel.com" , Xing Zhengjun Subject: Re: [mm/highmem] 61b205f579: WARNING:at_mm/highmem.c:#__kmap_local_sched_out Message-ID: <20210312062755.GA5022@xsang-OptiPlex-9020> References: <20210304083825.GB17830@xsang-OptiPlex-9020> <20210311160220.GS3014244@iweiny-DESK2.sc.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210311160220.GS3014244@iweiny-DESK2.sc.intel.com> User-Agent: Mutt/1.9.4 (2018-02-28) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Ira, On Thu, Mar 11, 2021 at 08:02:20AM -0800, Ira Weiny wrote: > On Tue, Mar 09, 2021 at 08:53:04PM +0000, Chaitanya Kulkarni wrote: > > Ira, > > > > On 3/4/21 00:23, kernel test robot wrote: > > > Greeting, > > > > > > FYI, we noticed the following commit (built with gcc-9): > > > > > > commit: 61b205f579911a11f0b576f73275eca2aed0d108 ("mm/highmem: Convert memcpy_[to|from]_page() to kmap_local_page()") > > > https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master > > > > > > > > > in testcase: trinity > > > version: trinity-static-i386-x86_64-f93256fb_2019-08-28 > > > with following parameters: > > > > > > runtime: 300s > > > > > > test-description: Trinity is a linux system call fuzz tester. > > > test-url: http://codemonkey.org.uk/projects/trinity/ > > > > > > > > > on test machine: qemu-system-i386 -enable-kvm -cpu SandyBridge -smp 2 -m 8G > > > > > > caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace): > > > > Is the fix for this been posted yet ? > > No. I've been unable to reproduce it yet. just FYI the issue does not always happen but the rate on 61b205f579 is not low, while we didn't observe it happen on parent commit. bb90d4bc7b6a536b 61b205f579911a11f0b576f7327 ---------------- --------------------------- fail:runs %reproduction fail:runs | | | :38 16% 6:38 dmesg.EIP:__kmap_local_sched_in :38 16% 6:38 dmesg.EIP:__kmap_local_sched_out :38 16% 6:38 dmesg.WARNING:at_mm/highmem.c:#__kmap_local_sched_in :38 16% 6:38 dmesg.WARNING:at_mm/highmem.c:#__kmap_local_sched_out also please permit me to quote our internal analysis by Zhengjun (cced) (Thanks a lot, Zhengjun) "the commit has the potential to cause the issue. It replaces " kmap_atomic" to " kmap_local_page". Most of the two API is the same, except for " kmap_atomic" disable preemption and cannot sleep. I check the issue happened when there is a preemption, in FBC " kmap_local_page", the preemption is enabled, the issue may happen." " > > Ira > > > > > (asking since I didn't see the fix and my mailer is dropping emails from > > lkml).