Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965547AbdCWQDE (ORCPT ); Thu, 23 Mar 2017 12:03:04 -0400 Received: from mail-qk0-f194.google.com ([209.85.220.194]:35179 "EHLO mail-qk0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965036AbdCWQDC (ORCPT ); Thu, 23 Mar 2017 12:03:02 -0400 Date: Fri, 24 Mar 2017 00:02:58 +0800 From: Ming Lei To: Dmitry Vyukov Cc: Jens Axboe , Hannes Reinecke , Mike Christie , Omar Sandoval , mnghuan@gmail.com, Petr Mladek , LKML , syzkaller Subject: Re: loop: WARNING in sysfs_remove_group Message-ID: <20170323160257.GA20432@ming.t460p> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.8.0 (2017-02-23) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1389 Lines: 33 On Thu, Mar 23, 2017 at 03:09:44PM +0100, Dmitry Vyukov wrote: > Hello, > > I've got the following WARNING while running syzkaller on > 093b995e3b55a0ae0670226ddfcb05bfbf0099ae. Note the preceding injected > kmalloc failure, most likely it's the root cause. > > FAULT_INJECTION: forcing a failure. > name failslab, interval 1, probability 0, space 0, times 0 > CPU: 3 PID: 21172 Comm: syz-executor4 Not tainted 4.11.0-rc3+ #364 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 > Call Trace: > __dump_stack lib/dump_stack.c:16 [inline] > dump_stack+0x1b8/0x28d lib/dump_stack.c:52 > fail_dump lib/fault-inject.c:45 [inline] > should_fail+0x78a/0x870 lib/fault-inject.c:154 > should_failslab+0xec/0x120 mm/failslab.c:31 > slab_pre_alloc_hook mm/slab.h:434 [inline] > slab_alloc mm/slab.c:3394 [inline] > kmem_cache_alloc+0x200/0x720 mm/slab.c:3570 > kmem_cache_zalloc include/linux/slab.h:653 [inline] > __kernfs_new_node+0xd1/0x430 fs/kernfs/dir.c:629 > kernfs_new_node+0x80/0xf0 fs/kernfs/dir.c:661 > kernfs_create_dir_ns+0x41/0x140 fs/kernfs/dir.c:933 > kernfs_create_dir include/linux/kernfs.h:477 [inline] > internal_create_group+0xf7/0x8f0 fs/sysfs/group.c:124 > sysfs_create_group+0x1f/0x30 fs/sysfs/group.c:156 > loop_sysfs_init drivers/block/loop.c:802 [inline] Looks we should have handled failure of loop_sys_init(). Thanks, Ming