My computer hangs since I’ve upgraded to 3.16.7-29. Downgrade to 3.16.7-24 resolved the issue :
2015-11-10T11:09:53.333557+01:00 Spirit org.a11y.Bus[2039]: Reloaded configuration
2015-11-10T11:09:55.651988+01:00 Spirit kernel: 6922.657045] BUG: workqueue leaked lock or atomic: kworker/0:1/0x7fffffff/19442
2015-11-10T11:09:55.652014+01:00 Spirit kernel: 6922.657045] last function: work_for_cpu_fn
2015-11-10T11:09:55.652018+01:00 Spirit kernel: 6922.657051] CPU: 0 PID: 19442 Comm: kworker/0:1 Tainted: G O 3.16.7-29-desktop #1
2015-11-10T11:09:55.652022+01:00 Spirit kernel: 6922.657053] Hardware name: /GA-M55PLUS-S3G, BIOS F15B 10/22/2008
2015-11-10T11:09:55.652025+01:00 Spirit kernel: 6922.657056] Workqueue: events work_for_cpu_fn
2015-11-10T11:09:55.652029+01:00 Spirit kernel: 6922.657058] ffff880065173d00 ffffffff8161c923 ffff88007bbf7ce0 ffffffff81077396
2015-11-10T11:09:55.652040+01:00 Spirit kernel: 6922.657060] 0000000081e18460 ffff88007fc11f40 ffff88007fc11f58 ffff880068d78350
2015-11-10T11:09:55.652043+01:00 Spirit kernel: 6922.657062] ffff880068d78350 ffff880065173d00 ffff880065173d30 ffffffff81077b2d
2015-11-10T11:09:55.652047+01:00 Spirit kernel: 6922.657064] Call Trace:
2015-11-10T11:09:55.652051+01:00 Spirit kernel: 6922.657078] <ffffffff810051ee>] dump_trace+0x8e/0x350
2015-11-10T11:09:55.652054+01:00 Spirit kernel: 6922.657082] <ffffffff81005556>] show_stack_log_lvl+0xa6/0x190
2015-11-10T11:09:55.652058+01:00 Spirit kernel: 6922.657086] <ffffffff81006c51>] show_stack+0x21/0x50
2015-11-10T11:09:55.652061+01:00 Spirit kernel: 6922.657091] <ffffffff8161c923>] dump_stack+0x49/0x6a
2015-11-10T11:09:55.652068+01:00 Spirit kernel: 6922.657096] <ffffffff81077396>] process_one_work+0x3e6/0x460
2015-11-10T11:09:55.652072+01:00 Spirit kernel: 6922.657102] <ffffffff81077b2d>] worker_thread+0x23d/0x510
2015-11-10T11:09:55.652075+01:00 Spirit kernel: 6922.657107] <ffffffff8107dd7d>] kthread+0xbd/0xe0
2015-11-10T11:09:55.652079+01:00 Spirit kernel: 6922.657111] <ffffffff81623558>] ret_from_fork+0x58/0x90
2015-11-10T11:09:55.652082+01:00 Spirit kernel: 6922.657120] BUG: workqueue leaked lock or atomic: kworker/0:1/0x7fffffff/19442
2015-11-10T11:09:55.652085+01:00 Spirit kernel: 6922.657120] last function: wq_barrier_func
2015-11-10T11:09:55.652089+01:00 Spirit kernel: 6922.657123] CPU: 0 PID: 19442 Comm: kworker/0:1 Tainted: G O 3.16.7-29-desktop #1
2015-11-10T11:09:55.652095+01:00 Spirit kernel: 6922.657124] Hardware name: /GA-M55PLUS-S3G, BIOS F15B 10/22/2008
2015-11-10T11:09:55.652099+01:00 Spirit kernel: 6922.657126] Workqueue: events wq_barrier_func
2015-11-10T11:09:55.652102+01:00 Spirit kernel: 6922.657127] ffff880065173d00 ffffffff8161c923 ffff88007bbf7c78 ffffffff81077396
2015-11-10T11:09:55.652106+01:00 Spirit kernel: 6922.657129] 0000000f81e18460 ffff88007fc11f40 ffff88007fc11f58 ffff880068d78350
2015-11-10T11:09:55.652109+01:00 Spirit kernel: 6922.657131] ffff880068d78350 ffff880065173d00 ffff880065173d30 ffffffff81077b2d
2015-11-10T11:09:55.652112+01:00 Spirit kernel: 6922.657133] Call Trace:
2015-11-10T11:09:55.652133+01:00 Spirit kernel: 6922.657137] <ffffffff810051ee>] dump_trace+0x8e/0x350
2015-11-10T11:09:55.652136+01:00 Spirit kernel: 6922.657141] <ffffffff81005556>] show_stack_log_lvl+0xa6/0x190
2015-11-10T11:09:55.652140+01:00 Spirit kernel: 6922.657143] <ffffffff81006c51>] show_stack+0x21/0x50
2015-11-10T11:09:55.652145+01:00 Spirit kernel: 6922.657146] <ffffffff8161c923>] dump_stack+0x49/0x6a
2015-11-10T11:09:55.652149+01:00 Spirit kernel: 6922.657149] <ffffffff81077396>] process_one_work+0x3e6/0x460
2015-11-10T11:09:55.652168+01:00 Spirit kernel: 6922.657154] <ffffffff81077b2d>] worker_thread+0x23d/0x510
2015-11-10T11:09:55.652172+01:00 Spirit kernel: 6922.657158] <ffffffff8107dd7d>] kthread+0xbd/0xe0
2015-11-10T11:09:55.652178+01:00 Spirit kernel: 6922.657160] <ffffffff81623558>] ret_from_fork+0x58/0x90
2015-11-10T11:09:55.652182+01:00 Spirit kernel: 6922.657165] BUG: scheduling while atomic: kworker/0:1/19442/0x00000000
2015-11-10T11:09:55.652186+01:00 Spirit kernel: 6922.657166] Modules linked in: vboxpci(O) vboxnetadp(O) vboxnetflt(O) vboxdrv(O) nls_utf8 isofs bnep bluetooth 6lowpan_iphc xt_REDIRECT xt_pkttype xt_LOG xt_limit iptable_nat nf_nat_ipv4 nf_nat xt_owner iscsi_ibft iscsi_boot_sysfs ip6t_REJECT xt_tcpudp nf_conntrack_ipv6 nf_defrag_ipv6 ip6table_raw ipt_REJECT iptable_raw xt_CT iptable_filter af_packet ip6table_mangle nf_conntrack_netbios_ns nf_conntrack_broadcast nf_conntrack_ipv4 nf_defrag_ipv4 ip_tables xt_conntrack nf_conntrack ip6table_filter ip6_tables x_tables cfg80211 rfkill fuse ppdev joydev snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec_hdmi powernow_k8 kvm_amd kvm pcspkr serio_raw k8temp edac_core edac_mce_amd snd_pcm_oss snd_hda_intel snd_hda_controller snd_hda_codec snd_hwdep snd_pcm snd_seq snd_seq_device snd_timer snd_mixer_oss snd forcedeth soundcore tpm_infineon tpm_tis tpm nv_tco i2c_nforce2 parport_pc parport shpchp button hid_logitech_dj radeon firewire_ohci firewire_core crc_itu_t i2c_algo_bit drm_kms_helper ttm ohci_pci drm sr_mod cdrom fan processor ata_generic pata_amd sata_nv dm_mirror dm_region_hash dm_log dm_mod sg [last unloaded: vboxdrv]