Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932843Ab3DBQWL (ORCPT ); Tue, 2 Apr 2013 12:22:11 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:38005 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932683Ab3DBQWJ (ORCPT ); Tue, 2 Apr 2013 12:22:09 -0400 Message-ID: <515B056E.6010002@oracle.com> Date: Tue, 02 Apr 2013 12:21:02 -0400 From: Sasha Levin User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130310 Thunderbird/17.0.4 MIME-Version: 1.0 To: koverstreet@google.com, NeilBrown CC: linux-bcache@vger.kernel.org, linux-raid@vger.kernel.org, "linux-kernel@vger.kernel.org" Subject: bcache: BUG in fuzz testing without devices Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Source-IP: ucsinet21.oracle.com [156.151.31.93] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2962 Lines: 53 Hi all, It seems that trying to fuzz bcache without any devices triggers a BUG: sh-4.2# echo 1 > /sys/fs/bcache/fuzz [ 89.700458] bio: create slab at 1 [ 89.704543] ------------[ cut here ]------------ [ 89.710043] kernel BUG at drivers/md/bcache/debug.c:447! [ 89.710043] invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC [ 89.710043] Modules linked in: [ 89.710043] CPU 2 [ 89.710043] Pid: 6885, comm: sh Tainted: G W 3.9.0-rc4-next-20130328-sasha-00017-g1463000 #321 [ 89.710043] RIP: 0010:[] [] btree_fuzz+0x95/0x720 [ 89.710043] RSP: 0018:ffff880035279be8 EFLAGS: 00010246 [ 89.710043] RAX: ffff880034720000 RBX: ffff880034721030 RCX: ffff8800353af400 [ 89.710043] RDX: 0000000000000000 RSI: ffff880034723b18 RDI: ffff88003477a960 [ 89.710043] RBP: ffff880035279e88 R08: ffff88003477a900 R09: ffff88003d801e00 [ 89.710043] R10: 000000000048d002 R11: 0000000000000000 R12: ffff880035279c18 [ 89.710043] R13: ffff880034721030 R14: ffff880034720000 R15: ffff880035279c30 [ 89.710043] FS: 00007f591db62700(0000) GS:ffff88003e000000(0000) knlGS:0000000000000000 [ 89.710043] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 89.710043] CR2: 00007f591db8e000 CR3: 0000000035bf0000 CR4: 00000000000406e0 [ 89.710043] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 89.710043] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 [ 89.710043] Process sh (pid: 6885, threadinfo ffff880035278000, task ffff880037060000) [ 89.710043] Stack: [ 89.710043] ffffffff84c1b104 ffffffff83e20320 000000000000d8e0 ffff880035279ca8 [ 89.710043] ffff88003e00a000 ffff880035278000 ffff880035279fd8 ffff88003e1d7cd0 [ 89.710043] ffff880035279c58 0000000000000000 0000000000000000 0000000000000000 [ 89.710043] Call Trace: [ 89.710043] [] ? sysfs_write_file+0xe2/0x150 [ 89.710043] [] kobj_attr_store+0xf/0x20 [ 89.710043] [] sysfs_write_file+0xfa/0x150 [ 89.710043] [] vfs_write+0xb0/0x180 [ 89.710043] [] SyS_write+0x50/0xa0 [ 89.710043] [] tracesys+0xe1/0xe6 [ 89.710043] Code: c0 49 89 c6 0f 84 2c 06 00 00 4c 8d a5 90 fd ff ff 4c 8d a8 30 10 00 00 4d 89 e7 49 83 c7 18 49 8b 9e 30 10 00 00 4c 39 eb 75 0b <0f> 0b 66 0f 1f 84 00 00 00 00 00 48 8d 83 a0 fd ff ff 48 89 df [ 89.710043] RIP [] btree_fuzz+0x95/0x720 [ 89.710043] RSP [ 89.755259] ---[ end trace d6647580839fba22 ]--- That BUG looks very intentional there, any reason for adding it instead of exiting if there aren't any devices? Thanks, Sasha -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/