Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S942855AbcJ0O3M (ORCPT ); Thu, 27 Oct 2016 10:29:12 -0400 Received: from mx1.redhat.com ([209.132.183.28]:52524 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S942648AbcJ0O3F (ORCPT ); Thu, 27 Oct 2016 10:29:05 -0400 Date: Thu, 27 Oct 2016 19:22:30 +0800 From: Xiong Zhou To: linux-nvdimm@ml01.01.org, jack@suse.cz Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: multi-threads libvmmalloc fork test hang Message-ID: <20161027112230.wsumgs62fqdxt3sc@xzhoul.usersys.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: NeoMutt/20161014 (1.7.0) X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.31]); Thu, 27 Oct 2016 11:22:31 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2856 Lines: 83 # description nvml test suite vmmalloc_fork test hang. $ ps -eo stat,comm | grep vmma S+ vmmalloc_fork Sl+ vmmalloc_fork Z+ vmmalloc_fork Sl+ vmmalloc_fork Z+ vmmalloc_fork Z+ vmmalloc_fork Sl+ vmmalloc_fork Z+ vmmalloc_fork Z+ vmmalloc_fork Z+ vmmalloc_fork dmesg: [ 250.499097] INFO: task vmmalloc_fork:9805 blocked for more than 120 seconds. [ 250.530667] Not tainted 4.9.09fe68ca+ #27 [ 250.550901] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 250.585752] vmmalloc_fork D[ 250.598362] ffffffff8171813c 0 9805 9765 0x00000080 [ 250.623445] ffff88075dc68f80[ 250.636052] 0000000000000000 ffff88076058db00 ffff88017c5b0000 ffff880763b19340[ 250.668510] ffffc9000fe1bbb0 ffffffff8171813c ffffc9000fe1bc20 ffffc9000fe1bbe0[ 250.704220] ffffffff82248898 ffff88076058db00 ffffffff82248898Call Trace: [ 250.738382] [] ? __schedule+0x21c/0x6a0 [ 250.763404] [] schedule+0x36/0x80 [ 250.786177] [] get_unlocked_mapping_entry+0xc1/0x120 [ 250.815869] [] ? iomap_dax_rw+0x110/0x110 [ 250.841350] [] grab_mapping_entry+0x4a/0x220 [ 250.868442] [] iomap_dax_fault+0xa9/0x3b0 [ 250.894437] [] xfs_filemap_fault+0xce/0xf0 [xfs] [ 250.922805] [] __do_fault+0x79/0x100 [ 250.947035] [] do_fault+0x49b/0x690 [ 250.970964] [] ? xfs_filemap_pmd_fault+0x9c/0x160 [xfs] [ 251.001812] [] handle_mm_fault+0x61a/0xa50 [ 251.027736] [] __do_page_fault+0x22a/0x4a0 [ 251.053700] [] do_page_fault+0x30/0x80 [ 251.077962] [] ? do_syscall_64+0x175/0x180 [ 251.103835] [] page_fault+0x28/0x30 # kernel versions: v4.6 pass in seconds v4.7 hang v4.9-rc1 hang Linus tree to commit 9fe68ca hang bisect points to first bad commit: [ac401cc782429cc8560ce4840b1405d603740917] dax: New fault locking v4.7 with these 3 commits reverted pass: 4d9a2c8 - Jan Kara, 6 months ago : dax: Remove i_mmap_lock protection bc2466e - Jan Kara, 6 months ago : dax: Use radix tree entry lock to protect cow faults ac401cc - Jan Kara, 6 months ago : dax: New fault locking # nvml version: https://github.com/pmem/nvml.git to commit: feab4d6f65102139ce460890c898fcad09ce20ae # How reproducible: always # Test steps: $cd nvml $make install -j64 $cat > src/test/testconfig.sh <