OVS with UEK4 crashes with blk_mq_tag_to_rq+0x21/0x70 (Doc ID 2187192.1)

Last updated on MARCH 08, 2017

Applies to:

Oracle VM - Version 3.4.1 and later
Information in this document applies to any platform.

Symptoms

On : 3.4.1 version, Dom0, HostOS, Management Domain

ACTUAL BEHAVIOR
---------------
OVS host crashed with below error

ERROR
-----------------------

[89269.484568] 10a32ed116: port 3(vif1.0-emu) entered forwarding state
[91107.176599] BUG: unable to handle kernel NULL pointer dereference at 00000000000000d8
[91107.177051] IP: [<ffffffff812ed901>] blk_mq_tag_to_rq+0x21/0x70
[91107.177457] PGD a0bcb7067 PUD 95f299067 PMD 0
[91107.177858] Oops: 0000 [#1] SMP
[91107.178258] Modules linked in: tun ocfs2 jbd2 nfsv3 nfs_acl nfs fscache lockd grace xen_pciback xen_netback xen_blkback xen_gntalloc xen_gntdev xen_evtchn ocfs2_dlmfs ocfs2_stack_o2cb ocfs2_dlm ocfs2_nodemanager ocfs2_stackglue configfs bnx2fc cnic uio fcoe libfcoe libfc sunrpc 8021q mrp garp bridge ipv6 stp llc bonding nf_conntrack_tftp nf_conntrack_netbios_ns nf_conntrack_broadcast ipt_REJECT nf_reject_ipv4 nf_conntrack_ipv4 nf_defrag_ipv4 xt_state nf_conntrack iptable_filter ip_tables xenfs xen_privcmd dm_round_robin scsi_dh_emc dm_multipath iTCO_wdt iTCO_vendor_support dcdbas pcspkr sb_edac edac_core lpc_ich mfd_core shpchp ipmi_devintf ipmi_si ipmi_msghandler sg igb ext3 jbd mbcache sr_mod cdrom sd_mod wmi ahci libahci megaraid_sas ixgbe dca ptp pps_core vxlan udp_tunnel ip6_udp_tunnel mdio
[91107.181320] lpfc scsi_transport_fc mgag200 ttm drm_kms_helper drm i2c_algo_bit sysimgblt sysfillrect i2c_core syscopyarea dm_mirror dm_region_hash dm_log dm_mod
[91107.182468] CPU: 18 PID: 0 Comm: swapper/18 Not tainted 4.1.12-32.1.3.el6uek.x86_64 #2
[91107.183074] Hardware name: Dell Inc. PowerEdge R920/0Y4CNC, BIOS 1.3.2 09/30/2014
[91107.183680] task: ffff880a260a9c00 ti: ffff880a260c0000 task.ti: ffff880a260c0000
[91107.184295] RIP: e030:[<ffffffff812ed901>] [<ffffffff812ed901>] blk_mq_tag_to_rq+0x21/0x70
[91107.184927] RSP: e02b:ffff880a31283d58 EFLAGS: 00010287
[91107.185560] RAX: ffff880a19ab0000 RBX: ffff880a19668400 RCX: 000000000000000c
[91107.186206] RDX: 0000000000000000 RSI: 00000000000005cc RDI: 0000000000000000
[91107.186857] RBP: ffff880a31283d68 R08: 000000000000000c R09: 0000000000001fc0
[91107.187509] R10: 0000000000000004 R11: 0000000000000000 R12: 00000000000005cc
[91107.188186] R13: 000000000000000c R14: ffff880a1d2925c0 R15: 0000000000000017
[91107.188846] FS: 0000000000000000(0000) GS:ffff880a31280000(0000) knlGS:0000000000000000
[91107.189512] CS: e033 DS: 002b ES: 002b CR0: 0000000080050033
[91107.190195] CR2: 00000000000000d8 CR3: 00000007c2ec0000 CR4: 0000000000042660
[91107.190878] Stack:
[91107.191558] ffff8800083b7800 00000000000005c0 ffff880a31283dc8 ffffffff812f1c11
[91107.192267] 0000000031283ea4 ffff880a31283e08 ffffffff812eea30 ffff880a1c4e2590
[91107.192981] 0000000000000000 ffff880a1c4e2580 ffff8800083b7800 ffff880a31283e08
[91107.193701] Call Trace:
[91107.194412] <IRQ>
[91107.194423] [<ffffffff812f1c11>] bt_for_each+0x81/0x100
[91107.195847] [<ffffffff812eea30>] ? blk_mq_complete_request+0x20/0x20
[91107.196574] [<ffffffff812eea30>] ? blk_mq_complete_request+0x20/0x20
[91107.197341] [<ffffffff812f1cf9>] blk_mq_tag_busy_iter+0x69/0x80
[91107.198064] [<ffffffff812ee501>] blk_mq_rq_timer+0x71/0x130
[91107.198766] [<ffffffff812ee490>] ? blk_mq_requeue_request+0x40/0x40
[91107.199462] [<ffffffff810e81b2>] call_timer_fn+0x42/0x120
[91107.200146] [<ffffffff810e8488>] run_timer_softirq+0x1f8/0x350
[91107.200837] [<ffffffff812ee490>] ? blk_mq_requeue_request+0x40/0x40
[91107.201532] [<ffffffff810844a2>] __do_softirq+0xf2/0x2f0
[91107.202223] [<ffffffff81084815>] irq_exit+0x125/0x130
[91107.202903] [<ffffffff813dd8b9>] xen_evtchn_do_upcall+0x39/0x50
[91107.203591] [<ffffffff816b961e>] xen_do_hypervisor_callback+0x1e/0x40
[91107.204287] <EOI>
[91107.204297] [<ffffffff810013aa>] ? xen_hypercall_sched_op+0xa/0x20
[91107.205684] [<ffffffff810013aa>] ? xen_hypercall_sched_op+0xa/0x20
[91107.206391] [<ffffffff8100a650>] ? xen_safe_halt+0x10/0x20
[91107.207090] [<ffffffff8101f98e>] ? default_idle+0x1e/0xc0
[91107.207775] [<ffffffff8101efdf>] ? arch_cpu_idle+0xf/0x20
[91107.208454] [<ffffffff810c45c5>] ? cpuidle_idle_call+0x135/0x1e0
[91107.209145] [<ffffffff810c4835>] ? cpu_idle_loop+0x1c5/0x1f0
[91107.209811] [<ffffffff810c487b>] ? cpu_startup_entry+0x1b/0x70
[91107.210456] [<ffffffff810c48bf>] ? cpu_startup_entry+0x5f/0x70
[91107.211074] [<ffffffff8101164a>] ? cpu_bringup_and_idle+0x2a/0x40
[91107.211670] Code: 4c 8b 6d f8 c9 c3 0f 1f 40 00 55 48 89 e5 41 54 53 0f 1f 44 00 00 48 8b 47 60 89 f2 41 89 f4 48 8b 1c d0 48 8b 7b 30 48 8b 53 38 <48> 8b 87 d8 00 00 00 48 85 c0 74 2b 8b 72 40 ff 50 08 48 8b 80
[91107.212923] RIP [<ffffffff812ed901>] blk_mq_tag_to_rq+0x21/0x70
[91107.213506] RSP <ffff880a31283d58>
[91107.214062] CR2: 00000000000000d8
[91107.215855] ------------[ cut here ]------------

 

Cause

Sign In with your My Oracle Support account

Don't have a My Oracle Support account? Click to get started

My Oracle Support provides customers with access to over a
Million Knowledge Articles and hundreds of Community platforms