Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755954AbbKRODZ (ORCPT ); Wed, 18 Nov 2015 09:03:25 -0500 Received: from mx1.redhat.com ([209.132.183.28]:49276 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755389AbbKRODU (ORCPT ); Wed, 18 Nov 2015 09:03:20 -0500 Message-ID: <1447855399.3974.24.camel@redhat.com> Subject: Re: kernel BUG at drivers/scsi/scsi_lib.c:1096! From: Mark Salter To: Michael Ellerman , "James E. J. Bottomley" , brking Cc: linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Date: Wed, 18 Nov 2015 09:03:19 -0500 In-Reply-To: <1447838334.1564.2.camel@ellerman.id.au> References: <1447838334.1564.2.camel@ellerman.id.au> Organization: Red Hat, Inc Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6966 Lines: 108 On Wed, 2015-11-18 at 20:18 +1100, Michael Ellerman wrote: > Hi folks, > > I'm intermittently seeing the following oops on at least one powerpc box. > > The BUG_ON() is from: > > static int scsi_init_sgtable(struct request *req, struct scsi_data_buffer *sdb) > { > ... > count = blk_rq_map_sg(req->q, req, sdb->table.sgl); > BUG_ON(count > sdb->table.nents); > > Looking at the dump it looks like count was 2, I can't work out what nents was. > > The machine's just a fairly boring bare metal setup, with a single IPR adapter: > > 0001:08:00.0 RAID bus controller: IBM PCI-E IPR SAS Adapter (ASIC) (rev 02) > Subsystem: IBM PCIe3 x8 SAS RAID Internal Adapter 6Gb (57D7) > Flags: bus master, fast devsel, latency 0 > Kernel driver in use: ipr > > > Anyone seen it before or have any ideas? I'm also seeing it on arm64 in 4.4-rc1 [    6.859003] Call trace:                                                                       [    6.861439] [] scsi_init_sgtable+0x84/0x88                                  [    6.867072] [] scsi_init_io+0x4c/0x1ac                                      [    6.872358] [] sd_setup_read_write_cmnd+0x44/0x844                          [    6.878682] [] sd_init_command+0x38/0xb0                                    [    6.884141] [] scsi_setup_cmnd+0xd8/0x13c                                   [    6.889686] [] scsi_prep_fn+0xc0/0x140                                      [    6.894973] [] blk_peek_request+0x148/0x24c                                 [    6.900692] [] scsi_request_fn+0x58/0x648                                   [    6.906237] [] __blk_run_queue+0x40/0x58                                    [    6.911696] [] blk_run_queue+0x30/0x48                                      [    6.916983] [] scsi_run_queue+0x204/0x294                                   [    6.922528] [] scsi_end_request+0x13c/0x1a0                                 [    6.928247] [] scsi_io_completion+0xf0/0x564                                [    6.934052] [] scsi_finish_command+0xe4/0x144                               [    6.939943] [] scsi_softirq_done+0x148/0x178                                [    6.945748] [] blk_done_softirq+0x7c/0x94                                   [    6.951295] [] __do_softirq+0x114/0x2a0                                     [    6.956667] [] irq_exit+0x8c/0xe4                                           [    6.961522] [] handle_IPI+0x170/0x228                                       [    6.966721] [] gic_handle_irq+0xa0/0xb8                                     [    6.972093] Exception stack(0xfffffe03dc143de0 to 0xfffffe03dc143f00)                         > > cheers > > > systemd[1]: Starting Uncomplicated firewall... >          Starting Uncomplicated firewall... > ------------[ cut here ]------------ > kernel BUG at drivers/scsi/scsi_lib.c:1096! > Oops: Exception in kernel mode, sig: 5 [#1] > SMP NR_CPUS=2048 NUMA PowerNV > Modules linked in: > CPU: 132 PID: 2699 Comm: kworker/132:1H Not tainted 4.4.0-rc1-54939-ge22a248-dirty #77 > Workqueue: kblockd cfq_kick_queue > task: c000000fef147400 ti: c000000feb384000 task.ti: c000000feb384000 > NIP: c0000000005ab4a8 LR: c0000000005ab490 CTR: 0000000000000000 > REGS: c000000feb387620 TRAP: 0700   Not tainted  (4.4.0-rc1-54939-ge22a248-dirty) > MSR: 9000000100029033   CR: 24002228  XER: 00000000 > CFAR: c000000000464950 SOFTE: 0 > GPR00: c0000000005ab490 c000000feb3878a0 c000000000d77d00 0000000000000002 > GPR04: c000000ff2030158 c000000ff47a0c00 0000000000000000 0000000000001000 > GPR08: 0000000000000000 0000000000000001 0000000000000000 fffffffffffffff7 > GPR12: 0000000000002200 c00000000fde5200 c0000000000c8098 c000000000b39858 > GPR16: c000000000ae12c8 c000000000b39948 0000000000000000 0000000000000000 > GPR20: c0000000005ab9c0 c0000017f5800144 0000000000000000 c000001e551a6850 > GPR24: c0000017f5800140 c0000007efb9c800 0000000000000000 c000001e551a6800 > GPR28: 0000000000000000 0000000000000000 c000000ff2030158 c000000feb420240 > NIP [c0000000005ab4a8] scsi_init_sgtable+0xa8/0x180 > LR [c0000000005ab490] scsi_init_sgtable+0x90/0x180 > Call Trace: > [c000000feb3878a0] [c0000000005ab490] scsi_init_sgtable+0x90/0x180 (unreliable) > [c000000feb3878e0] [c0000000005ab5d4] scsi_init_io+0x54/0x160 > [c000000feb387930] [c0000000005fb43c] sd_init_command+0x6c/0xb00 > [c000000feb3879f0] [c0000000005ac2f8] scsi_setup_cmnd+0x108/0x1a0 > [c000000feb387a30] [c0000000005ac594] scsi_prep_fn+0x104/0x1c0 > [c000000feb387a70] [c00000000045d85c] blk_peek_request+0x20c/0x390 > [c000000feb387af0] [c0000000005ad6a8] scsi_request_fn+0xb8/0x7f0 > [c000000feb387bf0] [c0000000004583b4] __blk_run_queue+0x54/0x80 > [c000000feb387c20] [c00000000047e178] cfq_kick_queue+0x38/0xc0 > [c000000feb387c50] [c0000000000c00cc] process_one_work+0x2ac/0x560 > [c000000feb387ce0] [c0000000000c0510] worker_thread+0x190/0x660 > [c000000feb387d80] [c0000000000c8198] kthread+0x108/0x130 > [c000000feb387e30] [c0000000000095b0] ret_from_kernel_thread+0x5c/0xac > Instruction dump: > 2fa30000 409e00e4 e8bf0000 e87e0030 7fc4f378 4beb91ed 60000000 813f0008 > 78630020 7f891840 7d301026 5529effe <0b090000> 907f0008 38600000 813e005c > ---[ end trace 3ea632a512ff48d5 ]--- > > -- > 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/ -- 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/