WARNING: at kernel/rcutree.c:1550 __rcu_process_callbacks+0x46f/0x4b0()

[Srivatsa S. Bhat]

Hi Paul,

While running a CPU hotplug stress test on v3.5-rc7+
(mainline commit 8a7298b7805ab) I hit this warning.
I haven't tried to debug this yet...

Line number 1550 maps to:

WARN_ON_ONCE(cpu_is_offline(smp_processor_id()));

inside rcu_do_batch().

Regards,
Srivatsa S. Bhat


[ 1206.095436] CPU 3 is now offline
[ 1206.097086] CPU 3 offline: Remove Rx thread
[ 1206.099133] CPU 2 MCA banks CMCI:0 CMCI:1 CMCI:3
[ 1206.103750] ------------[ cut here ]------------
[ 1206.103758] WARNING: at kernel/rcutree.c:1550 __rcu_process_callbacks+0x46f/0x4b0()
[ 1206.103759] Hardware name: 4180F59
[ 1206.103759] Modules linked in: tcp_lp lp ebtable_nat ebtables ipt_MASQUERADE iptable_nat nf_nat xt_CHECKSUM iptable_mangle bridge stp llc ppdev parport_pc parport fuse be2iscsi iscsi_boot_sysfs bnx2i cnic uio cxgb4i cxgb4 cxgb3i libcxgbi cxgb3 mdio ib_iser ip6t_ipv6header rdma_cm ib_cm iw_cm ib_sa lockd ip6t_REJECT ib_mad ib_core nf_conntrack_ipv6 nf_defrag_ipv6 xt_limit ib_addr iscsi_tcp nf_conntrack_ipv4 libiscsi_tcp libiscsi nf_defrag_ipv4 xt_state nf_conntrack scsi_transport_iscsi ip6table_filter ip6_tables snd_hda_codec_conexant snd_hda_intel snd_hda_codec snd_hwdep arc4 iwlwifi snd_seq snd_seq_device snd_pcm mac80211 snd_timer thinkpad_acpi snd sunrpc vhost_net macvtap uvcvideo macvlan tun videobuf2_core kvm_intel cfg80211 videodev media videobuf2_vmalloc tpm_tis kvm i2c_i801 e1000e joydev tpm videobuf2_memops soundcore snd_page_alloc rfkill lpc_ich mfd_core tpm_bios microcode binfmt_misc uinput sdhci_pci sdhci mmc_core nouveau i915 ttm drm_kms_helper drm mxm_wmi i2!
 c_algo_bit
 i2c_core video wmi
[ 1206.103829]  [last unloaded: scsi_wait_scan]
[ 1206.103832] Pid: 6217, comm: migration/1 Not tainted 3.5.0-rc7-mandeep #1
[ 1206.103833] Call Trace:
[ 1206.103834]  <IRQ>  [<ffffffff8106036f>] warn_slowpath_common+0x7f/0xc0
[ 1206.103840]  [<ffffffff810603ca>] warn_slowpath_null+0x1a/0x20
[ 1206.103843]  [<ffffffff81110d5f>] __rcu_process_callbacks+0x46f/0x4b0
[ 1206.103845]  [<ffffffff8108f894>] ? __run_hrtimer+0x84/0x3a0
[ 1206.103848]  [<ffffffff81697f47>] ? _raw_spin_unlock_irqrestore+0x77/0x80
[ 1206.103852]  [<ffffffff810998dd>] ? account_system_vtime+0xdd/0xf0
[ 1206.103855]  [<ffffffff81110dd3>] rcu_process_callbacks+0x33/0x290
[ 1206.103857]  [<ffffffff8106a638>] __do_softirq+0xc8/0x3e0
[ 1206.103860]  [<ffffffff8103bc2d>] ? lapic_next_event+0x1d/0x30
[ 1206.103863]  [<ffffffff816a26ec>] call_softirq+0x1c/0x30
[ 1206.103866]  [<ffffffff8101c365>] do_softirq+0xa5/0xe0
[ 1206.103870]  [<ffffffff8106acae>] irq_exit+0xbe/0xf0
[ 1206.103872]  [<ffffffff816a306e>] smp_apic_timer_interrupt+0x6e/0x99
[ 1206.103875]  [<ffffffff816a1cef>] apic_timer_interrupt+0x6f/0x80
[ 1206.103878]  <EOI>  [<ffffffff810ee2e3>] ? stop_machine_cpu_stop+0xc3/0x110
[ 1206.103883]  [<ffffffff810edf19>] cpu_stopper_thread+0xd9/0x1b0
[ 1206.103884]  [<ffffffff810ee220>] ? queue_stop_cpus_work+0xf0/0xf0
[ 1206.103893]  [<ffffffff816960b1>] ? __schedule+0x431/0xa20
[ 1206.103896]  [<ffffffff810cd21d>] ? trace_hardirqs_on_caller+0x11d/0x1b0
[ 1206.103900]  [<ffffffff810ede40>] ? cpu_stop_signal_done+0x40/0x40
[ 1206.103902]  [<ffffffff8108a86e>] kthread+0xae/0xc0
[ 1206.103905]  [<ffffffff810cd2bd>] ? trace_hardirqs_on+0xd/0x10
[ 1206.103908]  [<ffffffff816a25f4>] kernel_thread_helper+0x4/0x10
[ 1206.103911]  [<ffffffff816986f0>] ? retint_restore_args+0x13/0x13
[ 1206.103913]  [<ffffffff8108a7c0>] ? __init_kthread_worker+0x70/0x70
[ 1206.103916]  [<ffffffff816a25f0>] ? gs_change+0x13/0x13
[ 1206.103918] ---[ end trace cbc247c5c233d6e7 ]---
[ 1206.104125] CPU 1 is now offline

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/