uname -a
Linux rtg-Aspire-V3-571G 3.16.0-45-generic #60~14.04.1-Ubuntu SMP Fri Jul 24 21:16:23 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux

kern.log:

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Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188271] WARNING: CPU: 7 PID: 58 at /build/linux-lts-utopic-AIjdaQ/linux-lts-utopic-3.16.0/kernel/watchdog.c:265 watchdog_overflow_callback+0x9c/0xd0()
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188273] Watchdog detected hard LOCKUP on cpu 7
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188274] Modules linked in: ctr ccm pci_stub vboxpci(OE) vboxnetadp(OE) vboxnetflt(OE) vboxdrv(OE) bnep rfcomm nls_iso8859_1 ath3k btusb bluetooth 6lowpan_iphc uvcvideo videobuf2_vmalloc videobuf2_memops videobuf2_core v4l2_common videodev media snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic intel_rapl x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm crct10dif_pclmul arc4 crc32_pclmul snd_hda_intel snd_hda_controller snd_hda_codec ath9k snd_hwdep snd_pcm ath9k_common ghash_clmulni_intel ath9k_hw aesni_intel snd_seq_midi snd_seq_midi_event aes_x86_64 lrw snd_rawmidi gf128mul glue_helper ablk_helper ath cryptd snd_seq snd_seq_device mac80211 nouveau snd_timer serio_raw i915 cfg80211 mxm_wmi ttm drm_kms_helper lpc_ich snd drm mei_me mei soundcore i2c_algo_bit shpchp joydev parport_pc ppdev lp parport acer_wmi sparse_keymap wmi mac_hid video hid_generic usbhid hid psmouse ahci tg3 libahci sdhci_pci ptp sdhci pps_core
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188334] CPU: 7 PID: 58 Comm: migration/7 Tainted: G      D W  OE 3.16.0-45-generic #60~14.04.1-Ubuntu
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188336] Hardware name: Acer Aspire V3-571G/VA50_HC_CR, BIOS V2.11 12/25/2012
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188338]  0000000000000009 ffff88045f3c5c00 ffffffff81765ca1 ffff88045f3c5c48
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188340]  ffff88045f3c5c38 ffffffff8106de3d ffff8804489d8000 0000000000000000
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188343]  ffff88045f3c5d60 0000000000000000 ffff88045f3c5ef8 ffff88045f3c5c98
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188346] Call Trace:
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188347]  <NMI>  [<ffffffff81765ca1>] dump_stack+0x45/0x56
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188355]  [<ffffffff8106de3d>] warn_slowpath_common+0x7d/0xa0
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188358]  [<ffffffff8106deac>] warn_slowpath_fmt+0x4c/0x50
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188361]  [<ffffffff8111c42c>] watchdog_overflow_callback+0x9c/0xd0
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188365]  [<ffffffff81158a7d>] __perf_event_overflow+0x8d/0x230
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188370]  [<ffffffff81029e18>] ? x86_perf_event_set_period+0xe8/0x150
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188372]  [<ffffffff81159524>] perf_event_overflow+0x14/0x20
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188374]  [<ffffffff8103136d>] intel_pmu_handle_irq+0x1ed/0x3e0
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188377]  [<ffffffff81028b1b>] perf_event_nmi_handler+0x2b/0x50
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188380]  [<ffffffff810170d8>] nmi_handle+0x88/0x120
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188382]  [<ffffffff810176de>] default_do_nmi+0xde/0x140
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188384]  [<ffffffff81017830>] do_nmi+0xf0/0x160
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188388]  [<ffffffff81770752>] end_repeat_nmi+0x1a/0x1e
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188391]  [<ffffffff8176dde7>] ? _raw_spin_lock+0x37/0x50
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188393]  [<ffffffff8176dde7>] ? _raw_spin_lock+0x37/0x50
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188396]  [<ffffffff8176dde7>] ? _raw_spin_lock+0x37/0x50
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188397]  <<EOE>>  [<ffffffff8109f2df>] __migrate_task+0x8f/0x170
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188403]  [<ffffffff8101c449>] ? sched_clock+0x9/0x10
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188405]  [<ffffffff8109f3c0>] ? __migrate_task+0x170/0x170
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188407]  [<ffffffff8109f3e3>] migration_cpu_stop+0x23/0x30
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188411]  [<ffffffff811015be>] cpu_stopper_thread+0x7e/0x150
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188413]  [<ffffffff81769e6f>] ? __schedule+0x35f/0x7a0
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188416]  [<ffffffff8109888f>] smpboot_thread_fn+0xff/0x1b0
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188419]  [<ffffffff81098790>] ? SyS_setgroups+0x180/0x180
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188422]  [<ffffffff81091572>] kthread+0xd2/0xf0
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188425]  [<ffffffff810914a0>] ? kthread_create_on_node+0x1c0/0x1c0
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188428]  [<ffffffff8176e298>] ret_from_fork+0x58/0x90
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188430]  [<ffffffff810914a0>] ? kthread_create_on_node+0x1c0/0x1c0
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4925.188432] ---[ end trace bfcc9921b1e54f45 ]---
Aug  1 00:26:26 rtg-Aspire-V3-571G kernel: [ 4926.394887] ------------[ cut here ]------------