What a nice tool the journalctl command!, after making some research I have discovered following issues:
First I have many Kenel dumps related to the lib/idr.c, but it seems the computer does not crash, since there are addtional logs.
sep 19 15 ZENKaOS kernel: WARNING: CPU: 0 PID: 1434 at lib/idr.c idr_remove.part.6+0x243/0x250()
sep 19 15 ZENKaOS kernel: idr_remove called for id=1146904 which is not allocated.
sep 19 15 ZENKaOS kernel: Modules linked in: rfcomm rts5139(C) bnep uvcvideo videobuf2_vmalloc videobuf2_memops videobuf2_core videodev ath3k ecb media btusb bluetooth 6lowpan_iphc crc16 joydev mousedev acpi_call(O) nvram coretemp asus_nb_wmi asus_wmi sparse_keymap hwmon arc4 intel_rapl ath9k x86_pkg_temp_thermal intel_powerclamp ath9k_common ath9k_hw kvm_intel kvm iTCO_wdt iTCO_vendor_support crct10dif_pclmul ath crc32_pclmul ghash_clmulni_intel led_class aesni_intel mac80211 aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd microcode cfg80211 snd_hda_codec_hdmi evdev mac_hid pcspkr i915 rfkill snd_hda_codec_realtek snd_hda_codec_generic psmouse serio_raw wmi thermal snd_hda_intel drm_kms_helper snd_hda_controller snd_hda_codec drm snd_hwdep snd_pcm i2c_i801 battery intel_gtt tpm_tis snd_timer tpm i2c_algo_bit
sep 19 15 ZENKaOS kernel: snd video ac mei_me button soundcore i2c_core mei shpchp lpc_ich processor pci_stub vboxpci(O) vboxnetflt(O) vboxnetadp(O) vboxdrv(O) sg xfs libcrc32c sd_mod crc_t10dif crct10dif_common atkbd libps2 ahci libahci crc32c_intel ehci_pci ehci_hcd xhci_hcd libata scsi_mod usbcore usb_common i8042 serio
sep 19 15 ZENKaOS kernel: CPU: 0 PID: 1434 Comm: chrome Tainted: G WC O 3.15.10-1 #1
sep 19 15 ZENKaOS kernel: Hardware name: ASUSTeK Computer Inc. UX31E/UX31E, BIOS UX31E.214 08/14/2012
sep 19 15 ZENKaOS kernel: 0000000000000009 ffff880126fefcc8 ffffffff81500ab6 ffff880126fefd10
sep 19 15 ZENKaOS kernel: ffff880126fefd00 ffffffff8106328d ffff880126fefd80 ffff8800b0b9dcc8
sep 19 15 ZENKaOS kernel: ffff88013939ef28 ffff8800b0b9dcc8 ffff88013939ef00 ffff880126fefd60
sep 19 15 ZENKaOS kernel: Call Trace:
sep 19 15 ZENKaOS kernel: dump_stack+0x4d/0x6f
sep 19 15 ZENKaOS kernel: warn_slowpath_common+0x7d/0xa0
sep 19 15 ZENKaOS kernel: warn_slowpath_fmt+0x4c/0x50
sep 19 15 ZENKaOS kernel: idr_remove.part.6+0x243/0x250
sep 19 15 ZENKaOS kernel: idr_remove+0xd/0x10
sep 19 15 ZENKaOS kernel: shmem_evict_inode+0xa2/0x180
sep 19 15 ZENKaOS kernel: evict+0xb4/0x180
sep 19 15 ZENKaOS kernel: iput+0xf5/0x180
sep 19 15 ZENKaOS kernel: __dentry_kill+0x1a8/0x200
sep 19 15 ZENKaOS kernel: dput+0xa5/0x180
sep 19 15 ZENKaOS kernel: __fput+0x132/0x1e0
sep 19 15 ZENKaOS kernel: ____fput+0xe/0x10
sep 19 15 ZENKaOS kernel: task_work_run+0xbc/0xe0
sep 19 15 ZENKaOS kernel: do_notify_resume+0x8c/0xa0
sep 19 15 ZENKaOS kernel: int_signal+0x12/0x17
sep 19 15 ZENKaOS kernel: ------
Second there is a clear evidence about a crash just before some reboots in the following logs, that involved chrome and the Intel video library i965:
sep 19 15 ZENKaOS kernel: chrome: segfault at 200 ip 00007f6307e9ceb8 sp 00007fff85ef0d60 error 4 in i965_dri.so
sep 19 15 ZENKaOS kernel: chrome: segfault at 200 ip 00007fd027391eb8 sp 00007fffb1c69f90 error 4 in i965_dri.so
sep 19 15 ZENKaOS kernel: chrome: segfault at 200 ip 00007f11bb88beb8 sp 00007fff89556450 error 4 in i965_dri.so
sep 19 15 ZENKaOS ntpd_intres: host name not found: 0.pool.ntp.org
sep 19 15 ZENKaOS ntpd_intres: host name not found: 1.pool.ntp.org
sep 19 15 ZENKaOS ntpd_intres: host name not found: 2.pool.ntp.org
I tried to work without Chrome, but it didn help. At least I think I am correctly pointed that it seems to be a video issue.
I am using now firefox instead of Chrome, and I jumped into a Linux Next kernel. If you have any additional idea, please let me know.
Thank you