Kernel crashes

[G.M.]

Recently, Ubuntu moved to kernel 4.4.x. On my ASUS X751L, this results in my LVDS+external VGA displays to regularly go to sleep/energy saving mode (even when being actively used) or to "scramble". As a consequence, I reverted to kernel 4.2.0-35-generic. This worked very well until I dist-upgraded last thursday. Now, the computer crashes regularly, notably when it is (xscreensaver-)locked (mostly while executing the "molecule" (OpenGL) screensaver).

I'm not sure if the crash occurs because of kernel, xscreensaver or an mplayer script I run with cron to play a beep every hour (don't ask why...).

This is a critical crash, so I assume there is a security issue behind...

Some extracts of my syslog:

[computer working...]
Jul 8 17:55:05 user-X751LAB sSMTP[10137]: Sent mail for <email address hidden> (221 2.0.0 closing connection c74sm3677627wme.1 - gsmtp) uid=0 username=root outbytes=691
Jul 8 17:56:01 user-X751LAB CRON[15626]: (user) CMD (/home/user/Softs/alarm_bat.sh)
^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@
[computer rebooted...]
Jul 8 17:59:44 user-X751LAB rsyslogd: [origin software="rsyslogd" swVersion="8.16.0" x-pid="927" x-info="http://www.rsyslog.com"] start
Jul 8 17:59:44 user-X751LAB rsyslogd-2222: command 'KLogPermitNonKernelFacility' is currently not permitted - did you already set it via a RainerScript command (v6+ config)? [v8.16.0 try http://www.rsyslog.com/e/2222 ]
Jul 8 17:59:44 user-X751LAB rsyslogd: rsyslogd's groupid changed to 109

Jul 8 17:59:44 user-X751LAB sensors[1049]: Adapter: Virtual device
Jul 8 17:59:44 user-X751LAB sensors[1049]: temp1: +42.0°C (crit = +108.0°C)
Jul 8 17:59:44 user-X751LAB sensors[1049]: temp2: +27.8°C (crit = +105.0°C)
Jul 8 17:59:44 user-X751LAB sensors[1049]: temp3: +29.8°C (crit = +105.0°C)
Jul 8 17:59:44 user-X751LAB sensors[1049]: coretemp-isa-0000
Jul 8 17:59:44 user-X751LAB sensors[1049]: Adapter: ISA adapter
Jul 8 17:59:44 user-X751LAB sensors[1049]: Physical id 0: +45.0°C (high = +105.0°C, crit = +105.0°C)
Jul 8 17:59:44 user-X751LAB sensors[1049]: Core 0: +45.0°C (high = +105.0°C, crit = +105.0°C)
Jul 8 17:59:44 user-X751LAB sensors[1049]: Core 1: +45.0°C (high = +105.0°C, crit = +105.0°C)

Jul 8 17:59:51 user-X751LAB kernel: [ 50.525061] [drm:gen8_irq_handler [i915]] *ERROR* The master control interrupt lied (SDE)!
Jul 8 17:59:51 user-X751LAB kernel: [ 50.526028] [drm:gen8_irq_handler [i915]] *ERROR* The master control interrupt lied (SDE)!
Jul 8 17:59:51 user-X751LAB kernel: [ 50.526578] [drm:gen8_irq_handler [i915]] *ERROR* The master control interrupt lied (SDE)!
Jul 8 17:59:51 user-X751LAB kernel: [ 50.527439] [drm:gen8_irq_handler [i915]] *ERROR* The master control interrupt lied (SDE)!
Jul 8 17:59:51 user-X751LAB kernel: [ 50.527866] [drm:gen8_irq_handler [i915]] *ERROR* The master control interrupt lied (SDE)!
Jul 8 17:59:51 user-X751LAB kernel: [ 50.528311] [drm:gen8_irq_handler [i915]] *ERROR* The master control interrupt lied (SDE)!
Jul 8 17:59:51 user-X751LAB kernel: [ 50.528739] [drm:gen8_irq_handler [i915]] *ERROR* The master control interrupt lied (SDE)!
Jul 8 17:59:51 user-X751LAB kernel: [ 50.529184] [drm:gen8_irq_handler [i915]] *ERROR* The master control interrupt lied (SDE)!
Jul 8 17:59:51 user-X751LAB kernel: [ 50.529588] [drm:gen8_irq_handler [i915]] *ERROR* The master control interrupt lied (SDE)!
Jul 8 17:59:51 user-X751LAB kernel: [ 50.530410] [drm:gen8_irq_handler [i915]] *ERROR* The master control interrupt lied (SDE)!
Jul 8 17:59:51 user-X751LAB kernel: [ 50.530827] [drm:gen8_irq_handler [i915]] *ERROR* The master control interrupt lied (SDE)!
Jul 8 17:59:51 user-X751LAB kernel: [ 50.530965] [drm:gen8_irq_handler [i915]] *ERROR* The master control interrupt lied (SDE)!
Jul 8 17:59:51 user-X751LAB kernel: [ 50.533857] [drm:gen8_irq_handler [i915]] *ERROR* The master control interrupt lied (SDE)!
Jul 8 17:59:51 user-X751LAB kernel: [ 50.534398] [drm:gen8_irq_handler [i915]] *ERROR* The master control interrupt lied (SDE)!

Jul 8 18:01:31 user-X751LAB kernel: [ 151.296804] ------------[ cut here ]------------
Jul 8 18:01:31 user-X751LAB kernel: [ 151.296868] WARNING: CPU: 3 PID: 1095 at /build/linux-HVWSXI/linux-4.2.0/drivers/gpu/drm/i915/intel_uncore.c:620 hsw_unclaimed_reg_debug+0x6d/0x90 [i915]()
Jul 8 18:01:31 user-X751LAB kernel: [ 151.296871] Unclaimed register detected after reading register 0x22390
Jul 8 18:01:31 user-X751LAB kernel: [ 151.296872] Modules linked in: bnep pci_stub vboxpci(OE) vboxnetadp(OE) vboxnetflt(OE) vboxdrv(OE) xt_CHECKSUM iptable_mangle ipt_MASQUERADE nf_nat_masquerade_ipv4 iptable_nat nf_nat_ipv4 nf_nat nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack nf_conntrack ipt_REJECT nf_reject_ipv4 xt_tcpudp bridge stp llc ctr ccm ebtable_filter ebtables ip6table_filter ip6_tables iptable_filter ip_tables x_tables binfmt_misc nls_iso8859_1 ath9k_htc ath9k_common ath9k_hw ath drbg ansi_cprng dm_crypt uvcvideo videobuf2_vmalloc videobuf2_memops btusb videobuf2_core intel_rapl btrtl btbcm asus_nb_wmi snd_hda_codec_hdmi btintel v4l2_common bluetooth i915 asus_wmi x86_pkg_temp_thermal videodev intel_powerclamp sparse_keymap arc4 media coretemp kvm_intel drm_kms_helper kvm rtl8723be drm crct10dif_pclmul btcoexist crc32_pclmul i2c_algo_bit snd_hda_codec_realtek snd_soc_rt5640 aesni_intel aes_x86_64 rtl8723_common snd_soc_rl6231 rtl_pci snd_hda_codec_generic rtlwifi mac80211 snd_soc_core snd_hda_intel snd_hda_codec snd_hda_core snd_compress lrw gf128mul ac97_bus cfg80211 snd_hwdep snd_pcm_dmaengine snd_pcm glue_helper snd_seq_midi snd_seq_midi_event ablk_helper snd_rawmidi cryptd snd_seq joydev mei_me snd_seq_device snd_timer rtsx_pci_ms input_leds mei snd processor_thermal_device serio_raw lpc_ich memstick dw_dmac dw_dmac_core soundcore i2c_designware_platform snd_soc_sst_acpi shpchp 8250_dw int3400_thermal intel_soc_dts_iosf acpi_thermal_rel int3402_thermal tpm_crb spi_pxa2xx_platform i2c_designware_core int340x_thermal_zone acpi_pad mac_hid parport_pc ppdev lp parport autofs4 hid_generic usbhid psmouse rtsx_pci_sdmmc ahci r8169 libahci rtsx_pci mii wmi sdhci_acpi video sdhci i2c_hid hid
Jul 8 18:01:31 user-X751LAB kernel: [ 151.296963] CPU: 3 PID: 1095 Comm: Xorg Tainted: G OE 4.2.0-35-generic #40-Ubuntu
Jul 8 18:01:31 user-X751LAB kernel: [ 151.296965] Hardware name: ASUSTeK COMPUTER INC. X751LAB/X751LAB, BIOS X751LAB.504 08/10/2015
Jul 8 18:01:31 user-X751LAB kernel: [ 151.296966] 0000000000000086 00000000a9ebe914 ffff88011ed83c68 ffffffff817f1d7e
Jul 8 18:01:31 user-X751LAB kernel: [ 151.296969] ffff88011ed83cc0 ffffffffc07329a0 ffff88011ed83ca8 ffffffff8107cb46
Jul 8 18:01:31 user-X751LAB kernel: [ 151.296971] ffff8800d8c8bcb0 ffff8800cf810000 0000000000022390 0000000000000001
Jul 8 18:01:31 user-X751LAB kernel: [ 151.296973] Call Trace:
Jul 8 18:01:31 user-X751LAB kernel: [ 151.296974] <IRQ> [<ffffffff817f1d7e>] dump_stack+0x63/0x81
Jul 8 18:01:31 user-X751LAB kernel: [ 151.296995] [<ffffffff8107cb46>] warn_slowpath_common+0x86/0xc0
Jul 8 18:01:31 user-X751LAB kernel: [ 151.296997] [<ffffffff8107cbd5>] warn_slowpath_fmt+0x55/0x70
Jul 8 18:01:31 user-X751LAB kernel: [ 151.297032] [<ffffffffc06b381d>] hsw_unclaimed_reg_debug+0x6d/0x90 [i915]
Jul 8 18:01:31 user-X751LAB kernel: [ 151.297054] [<ffffffffc06b6021>] gen6_read32+0xd1/0x1a0 [i915]
Jul 8 18:01:31 user-X751LAB kernel: [ 151.297077] [<ffffffffc06aae08>] intel_lrc_irq_handler+0xc8/0x220 [i915]
Jul 8 18:01:31 user-X751LAB kernel: [ 151.297097] [<ffffffffc06a1907>] gen8_gt_irq_handler+0x217/0x240 [i915]
Jul 8 18:01:31 user-X751LAB kernel: [ 151.297117] [<ffffffffc06a19ce>] gen8_irq_handler+0x9e/0x590 [i915]
Jul 8 18:01:31 user-X751LAB kernel: [ 151.297122] [<ffffffff810d633f>] handle_irq_event_percpu+0x7f/0x1c0
Jul 8 18:01:31 user-X751LAB kernel: [ 151.297124] [<ffffffff810d64c9>] handle_irq_event+0x49/0x70
Jul 8 18:01:31 user-X751LAB kernel: [ 151.297127] [<ffffffff810d9861>] handle_edge_irq+0x81/0x150
Jul 8 18:01:31 user-X751LAB kernel: [ 151.297130] [<ffffffff81018325>] handle_irq+0x25/0x40
Jul 8 18:01:31 user-X751LAB kernel: [ 151.297134] [<ffffffff817fb86f>] do_IRQ+0x4f/0xe0
Jul 8 18:01:31 user-X751LAB kernel: [ 151.297137] [<ffffffff817f97eb>] common_interrupt+0x6b/0x6b
Jul 8 18:01:31 user-X751LAB kernel: [ 151.297138] <EOI> [<ffffffffc0691201>] ? i915_gem_obj_to_ggtt_view+0x51/0x110 [i915]
Jul 8 18:01:31 user-X751LAB kernel: [ 151.297177] [<ffffffffc069268d>] i915_gem_object_ggtt_unpin_view+0x1d/0xa0 [i915]
Jul 8 18:01:31 user-X751LAB kernel: [ 151.297193] [<ffffffffc0684f1d>] i915_gem_do_execbuffer.isra.27+0x7dd/0x10a0 [i915]
Jul 8 18:01:31 user-X751LAB kernel: [ 151.297198] [<ffffffff816d1b9e>] ? sock_def_readable+0x3e/0x70
Jul 8 18:01:31 user-X751LAB kernel: [ 151.297202] [<ffffffff811e1deb>] ? __kmalloc+0x1cb/0x270
Jul 8 18:01:31 user-X751LAB kernel: [ 151.297220] [<ffffffffc0686912>] i915_gem_execbuffer2+0xb2/0x240 [i915]
Jul 8 18:01:31 user-X751LAB kernel: [ 151.297240] [<ffffffffc04cf505>] drm_ioctl+0x125/0x610 [drm]
Jul 8 18:01:31 user-X751LAB kernel: [ 151.297256] [<ffffffffc0686860>] ? i915_gem_execbuffer+0x310/0x310 [i915]
Jul 8 18:01:31 user-X751LAB kernel: [ 151.297260] [<ffffffff81213cd5>] do_vfs_ioctl+0x295/0x480
Jul 8 18:01:31 user-X751LAB kernel: [ 151.297263] [<ffffffff81213f39>] SyS_ioctl+0x79/0x90
Jul 8 18:01:31 user-X751LAB kernel: [ 151.297266] [<ffffffff817f8c72>] entry_SYSCALL_64_fastpath+0x16/0x75
Jul 8 18:01:31 user-X751LAB kernel: [ 151.297268] ---[ end trace f020f26a2c6a6513 ]---

WORKAROUND: Remove the following packages:
xscreensaver-gl*
xscreensaver-data-extra

[Steve Beattie (sbeattie)]

Thanks for taking the time to report this bug and helping to make Ubuntu better. We appreciate the difficulties you are facing, but this appears to be a "regular" (non-security) bug. I have unmarked it as a security issue since this bug does not show evidence of allowing attackers to cross privilege boundaries nor directly cause loss of data/privacy. Please feel free to report any other bugs you may find.

[Brad Figg (brad-figg)]

This bug is missing log files that will aid in diagnosing the problem. From a terminal window please run:

apport-collect 1600759

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.

This change has been made by an automated script, maintained by the Ubuntu Kernel Team.

[G.M. (sexxxenator)]

Hi again,

@brad-figg: Since whole computer is totally frozen (even SysReq keys do not work), I indeed cannot run apport.

@sbeattie: since the problem resides in the kernel, and the computer is totally frozen, I assumed that this was a security issue, as an attacker could locally/remotely freeze the computer... But if you say it is not, I'll trust you...

FYI, I removed the xscreensaver-gl* and xscreensaver-data-extra and the problem disappeared. I'm thus convinced to bug can be found in the video driver, when some OpenGL command is run.

[penalvch (penalvch)]

G.M., with the WORKAROUND in place, please execute the following command only once, as it will automatically gather debugging information, in a terminal:
apport-collect 1600759

[Launchpad Janitor (janitor)]

[Expired for linux (Ubuntu) because there has been no activity for 60 days.]