From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stefan Priebe - Profihost AG Subject: sd_setup_discard_cmnd: BUG: unable to handle kernel NULL pointer dereference at (null) Date: Thu, 19 Jun 2014 09:02:57 +0200 Message-ID: <53A28B21.7070500@profihost.ag> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Return-path: Received: from mail-ph.de-nserver.de ([85.158.179.214]:35395 "EHLO mail-ph.de-nserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753396AbaFSHI2 (ORCPT ); Thu, 19 Jun 2014 03:08:28 -0400 Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: NeilBrown Cc: linux-raid@vger.kernel.org, linux-scsi , JBottomley@parallels.com, Jens Axboe , konrad.wilk@oracle.com, elder@linaro.org, Josh Durgin , Greg KH , Lars Ellenberg Hi, while using vanilla 3.10.44 with drbd on top of a md raid1. I'm pretty often hitting the followin kernel bug. It reminds me of: http://lists.openwall.net/linux-kernel/2014/02/19/428 But i don't use bcache. [sched_delayed] sched: RT throttling activated BUG: unable to handle kernel NULL pointer dereference at (null) IP: [] blk_add_request_payload+0xc/0x90 PGD 0 Oops: 0002 [#1] SMP Modules linked in: vhost_net tun macvtap macvlan dlm sctp netconsole drbd lru_cache xt_multiport iptable_filter ip_tables x_tables iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi nfsd auth_rpcgss oid_registry bonding ext2 8021q garp fuse acpi_cpufreq mperf coretemp kvm_intel kvm microcode i2c_i801 i7core_edac edac_core button dm_mod raid1 md_mod usb_storage ohci_hcd usbhid sg sd_mod uhci_hcd ehci_pci ehci_hcd ahci libahci usbcore ixgbe(O) usb_common igb i2c_algo_bit mpt2sas i2c_core raid_class ptp scsi_transport_sas pps_core CPU: 0 PID: 636 Comm: md124_raid1 Tainted: G O 3.10.41+76-ph #1 Hardware name: Supermicro X8DT3/X8DT3, BIOS 2.1 03/17/2012 task: ffff880811e16400 ti: ffff88081324c000 task.ti: ffff88081324c000 RIP: 0010:[] [] blk_add_request_payload+0xc/0x90 RSP: 0018:ffff88081324dac8 EFLAGS: 00010086 RAX: ffff88080b686b40 RBX: ffff88080af19028 RCX: 0000000000000000 RDX: 0000000000000018 RSI: ffffea00202b7200 RDI: ffff88080af19028 RBP: ffff88081324dac8 R08: ffffea00202b7200 R09: 00000000006f4a62 R10: 000000000000243d R11: 0000000000000000 R12: ffff8808145b9400 R13: ffff8810139a6000 R14: 0000000004400000 R15: ffff88080adc8000 FS: 0000000000000000(0000) GS:ffff88081fc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 0000000000000000 CR3: 0000000001a0b000 CR4: 00000000000007f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400Stack: ffff88081324db18 ffffffffa01b515f ffffea00202b7200 000000000b637800 ffff88081324db18 ffff88080af19028 ffff880812f18818 ffff88081324dca8 ffff8810139a6000 ffff8808145b9800 ffff88081324db88 ffffffffa01b5318 Call Trace: [] sd_setup_discard_cmnd+0x13f/0x260 [sd_mod] [] sd_prep_fn+0x98/0xbb0 [sd_mod] [] ? merge+0x50/0xa0 [] ? blk_start_plug+0x50/0x50 [] blk_peek_request+0x132/0x250 [] scsi_request_fn+0x46/0x520 [] __blk_run_queue+0x32/0x40 [] queue_unplugged+0x34/0xb0 [] blk_flush_plug_list+0x183/0x220 [] blk_finish_plug+0x13/0x50 [] raid1d+0x706/0xee0 [raid1] [] ? try_to_del_timer_sync+0x4a/0x60 [] ? del_timer_sync+0x52/0x60 [] ? usleep_range+0x40/0x40 [] md_thread+0x11d/0x170 [md_mod] [] ? finish_wait+0x80/0x80 Stefan