Did this issue start happening after an update/upgrade?  Was there a
prior kernel version where you were not having this particular problem?
>>Its a new machine.
>>I located another machine with exact same hardware, ubuntu build and
drivers which is manifesting no problems: therefore this is a hardware bug
or at worst a bad interaction of OS with damaged hardware.




On 16 December 2015 at 19:27, Joseph Salisbury <
<email address hidden>> wrote:

> Did this issue start happening after an update/upgrade?  Was there a
> prior kernel version where you were not having this particular problem?
>
> Would it be possible for you to test the latest upstream kernel? Refer
> to https://wiki.ubuntu.com/KernelMainlineBuilds . Please test the latest
> v4.4 kernel[0].
>
> If this bug is fixed in the mainline kernel, please add the following
> tag 'kernel-fixed-upstream'.
>
> If the mainline kernel does not fix this bug, please add the tag:
> 'kernel-bug-exists-upstream'.
>
> Once testing of the upstream kernel is complete, please mark this bug as
> "Confirmed".
>
>
> Thanks in advance.
>
> [0] http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.4-rc5-wily
>
>
> ** Changed in: linux (Ubuntu)
>    Importance: Undecided => Medium
>
> ** Changed in: linux (Ubuntu)
>        Status: Confirmed => Incomplete
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1526657
>
> Title:
>   desktop freeze, htop shows kernel thread at 100% cpu
>
> Status in linux package in Ubuntu:
>   Incomplete
>
> Bug description:
>   Every few hours the desktop freezes.  I can still login via ssh, htop
>   shows one process running at 100%.  The process is shown in red,
>   indicating a kernel thread.   No response to ctrl-alt-f1  or to
>   service lightdm restart.
>
>   Graphics card is NVIDIA NVS 310.
>
>   I've tried the NVIDIA drivers in various versions up to nvidia-
>   current, and also nouveau (current bug report is with logfiles etc
>   generated after a crash while running nouveau).
>
>   Xorg.log shows a seg fault:
>
>   [171809.988] (EE)
>   [171809.988] (EE) Backtrace:
>   [171809.988] (EE) 0: /usr/bin/X (xorg_backtrace+0x48) [0x7fc8b9ccd848]
>   [171809.988] (EE) 1: /usr/bin/X (0x7fc8b9b24000+0x1ad539)
> [0x7fc8b9cd1539]
>   [171809.988] (EE) 2: /lib/x86_64-linux-gnu/libpthread.so.0
> (0x7fc8b8c20000+0x10340) [0x7fc8b8c30340]
>   [171809.988] (EE) 3: /lib/x86_64-linux-gnu/libc.so.6
> (0x7fc8b763f000+0x97ff0) [0x7fc8b76d6ff0]
>   [171809.988] (EE) 4: /usr/lib/xorg/modules/libexa.so
> (0x7fc8b295f000+0x5356) [0x7fc8b2964356]
>   [171809.988] (EE) 5: /usr/lib/xorg/modules/libexa.so
> (0x7fc8b295f000+0x57fb) [0x7fc8b29647fb]
>   [171809.988] (EE) 6: /usr/lib/xorg/modules/libexa.so
> (0x7fc8b295f000+0x7e22) [0x7fc8b2966e22]
>   [171809.988] (EE) 7: /usr/lib/xorg/modules/libexa.so
> (0x7fc8b295f000+0x1186a) [0x7fc8b297086a]
>   [171809.988] (EE) 8: /usr/lib/xorg/modules/libexa.so
> (0x7fc8b295f000+0xe236) [0x7fc8b296d236]
>   [171809.988] (EE) 9: /usr/lib/xorg/modules/libexa.so
> (0x7fc8b295f000+0xc028) [0x7fc8b296b028]
>   [171809.988] (EE) 10: /usr/bin/X (0x7fc8b9b24000+0x133f56)
> [0x7fc8b9c57f56]
>   [171809.988] (EE) 11: /usr/bin/X (0x7fc8b9b24000+0x12a3fe)
> [0x7fc8b9c4e3fe]
>   [171809.988] (EE) 12: /usr/bin/X (0x7fc8b9b24000+0x55f0e)
> [0x7fc8b9b79f0e]
>   [171809.988] (EE) 13: /usr/bin/X (0x7fc8b9b24000+0x59d9a)
> [0x7fc8b9b7dd9a]
>   [171809.988] (EE) 14: /lib/x86_64-linux-gnu/libc.so.6
> (__libc_start_main+0xf5) [0x7fc8b7660ec5]
>   [171809.988] (EE) 15: /usr/bin/X (0x7fc8b9b24000+0x451ee)
> [0x7fc8b9b691ee]
>   [171809.988] (EE)
>   [171809.988] (EE) Segmentation fault at address 0x0
>   [171809.988] (EE)
>   Fatal server error:
>   [171809.988] (EE) Caught signal 11 (Segmentation fault). Server aborting
>   [171809.988] (EE)
>
>   ProblemType: Bug
>   DistroRelease: Ubuntu 14.04
>   Package: linux-image-3.13.0-71-generic 3.13.0-71.114
>   ProcVersionSignature: Ubuntu 3.13.0-71.114-generic 3.13.11-ckt29
>   Uname: Linux 3.13.0-71-generic x86_64
>   ApportVersion: 2.14.1-0ubuntu3.19
>   Architecture: amd64
>   AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/by-path',
> '/dev/snd/controlC1', '/dev/snd/hwC1D0', '/dev/snd/pcmC1D3p',
> '/dev/snd/pcmC1D7p', '/dev/snd/controlC0', '/dev/snd/hwC0D0',
> '/dev/snd/pcmC0D0c', '/dev/snd/pcmC0D0p', '/dev/snd/seq', '/dev/snd/timer']
> failed with exit code 1:
>   Date: Wed Dec 16 08:30:46 2015
>   DistributionChannelDescriptor:
>    # This is a distribution channel descriptor
>    # For more information see
> http://wiki.ubuntu.com/DistributionChannelDescriptor
>    canonical-oem-somerville-precise-amd64-20130203-1
>   InstallationDate: Installed on 2015-10-17 (59 days ago)
>   InstallationMedia: Ubuntu 12.04 "Precise" - Build amd64 LIVE Binary
> 20130203-13:50
>   IwConfig:
>    eth0      no wireless extensions.
>
>    eth1      no wireless extensions.
>
>    lo        no wireless extensions.
>   MachineType: Dell Inc. Precision Tower 7910
>   ProcFB: 0 nouveaufb
>   ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.13.0-71-generic
> root=UUID=8fb5292d-6961-420e-ac9b-3f468520a7de ro plymouth:debug splash
> quiet drm.debug=0xe
>   PulseList: Error: command ['pacmd', 'list'] failed with exit code 1: No
> PulseAudio daemon running, or not running as session daemon.
>   RelatedPackageVersions:
>    linux-restricted-modules-3.13.0-71-generic N/A
>    linux-backports-modules-3.13.0-71-generic  N/A
>    linux-firmware                             1.127.19
>   RfKill:
>
>   SourcePackage: linux
>   UpgradeStatus: Upgraded to trusty on 2015-11-02 (43 days ago)
>   dmi.bios.date: 09/26/2015
>   dmi.bios.vendor: Dell Inc.
>   dmi.bios.version: A09
>   dmi.board.name: 0215PR
>   dmi.board.vendor: Dell Inc.
>   dmi.board.version: A03
>   dmi.chassis.type: 7
>   dmi.chassis.vendor: Dell Inc.
>   dmi.modalias:
> dmi:bvnDellInc.:bvrA09:bd09/26/2015:svnDellInc.:pnPrecisionTower7910:pvr:rvnDellInc.:rn0215PR:rvrA03:cvnDellInc.:ct7:cvr:
>   dmi.product.name: Precision Tower 7910
>   dmi.sys.vendor: Dell Inc.
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1526657/+subscriptions
>