From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755910AbdIRMOc (ORCPT ); Mon, 18 Sep 2017 08:14:32 -0400 Received: from mail-wm0-f65.google.com ([74.125.82.65]:38113 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755115AbdIRMO0 (ORCPT ); Mon, 18 Sep 2017 08:14:26 -0400 X-Google-Smtp-Source: AOwi7QChBZENkXEMYW1trZdG7HaPpbjBdYZP0QQ1fZuedQyYi5W4PChNtkhaDKCFmnI63FZ/roAoTw== From: Michal Hocko To: Andrew Morton Cc: Dan Williams , LKML , , Michal Hocko , Johannes Thumshirn Subject: [PATCH 2/3] mm, page_alloc: add scheduling point to memmap_init_zone Date: Mon, 18 Sep 2017 14:14:09 +0200 Message-Id: <20170918121410.24466-3-mhocko@kernel.org> X-Mailer: git-send-email 2.14.1 In-Reply-To: <20170918121410.24466-1-mhocko@kernel.org> References: <20170918121410.24466-1-mhocko@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Michal Hocko memmap_init_zone gets a pfn range to intialize and it can be really large resulting in a soft lockup on non-preemptible kernels [ 65.585596] NMI watchdog: BUG: soft lockup - CPU#31 stuck for 23s! [kworker/u642:5:1720] [...] [ 65.585818] task: ffff88ecd7e902c0 ti: ffff88eca4e50000 task.ti: ffff88eca4e50000 [ 65.585819] RIP: 0010:[] [] move_pfn_range_to_zone+0x185/0x1d0 [...] [ 65.585843] Call Trace: [ 65.585853] [] devm_memremap_pages+0x2c7/0x430 [ 65.585862] [] pmem_attach_disk+0x2fd/0x3f0 [nd_pmem] [ 65.585893] [] nvdimm_bus_probe+0x64/0x110 [libnvdimm] [ 65.585904] [] driver_probe_device+0x1f7/0x420 [ 65.585910] [] bus_for_each_drv+0x52/0x80 [ 65.585913] [] __device_attach+0xb0/0x130 [ 65.585916] [] bus_probe_device+0x87/0xa0 [ 65.585919] [] device_add+0x3fc/0x5f0 [ 65.585924] [] nd_async_device_register+0xe/0x40 [libnvdimm] [ 65.585927] [] async_run_entry_fn+0x43/0x150 [ 65.585933] [] process_one_work+0x14e/0x410 [ 65.585937] [] worker_thread+0x116/0x490 [ 65.585939] [] kthread+0xc7/0xe0 [ 65.585943] [] ret_from_fork+0x3f/0x70 Fix this by adding a scheduling point once per page block. Reported-by: Johannes Thumshirn Signed-off-by: Michal Hocko --- mm/page_alloc.c | 1 + 1 file changed, 1 insertion(+) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index fc36755a21cf..41e93dfc702e 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -5320,6 +5320,7 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone, __init_single_page(page, pfn, zone, nid); set_pageblock_migratetype(page, MIGRATE_MOVABLE); + cond_resched(); } else { __init_single_pfn(pfn, zone, nid); } -- 2.14.1