BUG: unable to handle kernel NULL pointer dereference

[Mail-fabian-keller]

System: Ubuntu 14.04
Graphics Card: Geforce GTX 670
Graphics Driver: nvidia-352.55

Starting with kernel 3.13.0-66, the start of X / default display manager results in a black screen. My observations are:
- When I get this black screen, I cannot CTRL+ALT+F1 into a text console
- Pressing the power button in this state leads to a proper shutdown (which I guess means that it is not a complete kernel panic).
- When using these latest kernel, the graphics behavior during boot-up also has changed. Instead of a graphical animation, the system boots in text mode (I can see the syslog output), and at the moment I should get the display manager, the screen goes black.

My work-around so far has been to boot kernel 3.13.0-65 instead of 3.13.0-66, 3.13.0-67, or 3.13.0-68. So far this has worked reliably. However today, booting kernel 3.13.0-65 has resulted in a black screen as well. Fortunately, I found a new work-around: I can boot kernel 3.13.0-68 in recovery mode, and chose simply "continue" in the recovery console. With this modification of the boot process, X will start.

In the syslog, I can see some suspicious messages, around the time X should start: "BUG: unable to handle kernel NULL pointer dereference at (null)". I have attached a syslog contain some failed starts as well as a successful one.

Another suspicion is that the problem is related having an Oculus Rift DK2 connected. In particular, this requires to use a custom Xorg.conf which runs individual X screens for the main display and the Oculus Rift.
---
ApportVersion: 2.14.1-0ubuntu3.18
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC1: fabian 2526 F.... pulseaudio
 /dev/snd/controlC0: fabian 2526 F.... pulseaudio
CurrentDesktop: Unity
DistroRelease: Ubuntu 14.04
HibernationDevice: RESUME=UUID=dfcf8d87-ab70-490e-922d-2ccfd8acdfcc
InstallationDate: Installed on 2014-04-24 (569 days ago)
InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Release amd64 (20140417)
IwConfig:
 eth0 no wireless extensions.

 lo no wireless extensions.
MachineType: MSI MS-7816
NonfreeKernelModules: nvidia
Package: linux (not installed)
ProcFB:

ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.13.0-68-generic root=UUID=58115c9d-156a-4608-9adb-e20d7ffc9b11 ro recovery nomodeset
ProcVersionSignature: Ubuntu 3.13.0-68.111-generic 3.13.11-ckt27
RelatedPackageVersions:
 linux-restricted-modules-3.13.0-68-generic N/A
 linux-backports-modules-3.13.0-68-generic N/A
 linux-firmware 1.127.18
RfKill:

Tags: trusty
Uname: Linux 3.13.0-68-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo
_MarkForUpload: True
dmi.bios.date: 05/17/2013
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: V1.2
dmi.board.asset.tag: To be filled by O.E.M.
dmi.board.name: Z87-G43 (MS-7816)
dmi.board.vendor: MSI
dmi.board.version: 1.0
dmi.chassis.asset.tag: To Be Filled By O.E.M.
dmi.chassis.type: 3
dmi.chassis.vendor: MSI
dmi.chassis.version: 1.0
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrV1.2:bd05/17/2013:svnMSI:pnMS-7816:pvr1.0:rvnMSI:rnZ87-G43(MS-7816):rvr1.0:cvnMSI:ct3:cvr1.0:
dmi.product.name: MS-7816
dmi.product.version: 1.0
dmi.sys.vendor: MSI

[Ubuntu Foundations Team Bug Bot (crichton)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. It seems that your bug report is not filed about a specific source package though, rather it is just filed against Ubuntu in general. It is important that bug reports be filed about source packages so that people interested in the package can find the bugs about it. You can find some hints about determining what package your bug might be about at https://wiki.ubuntu.com/Bugs/FindRightPackage. You might also ask for help in the #ubuntu-bugs irc channel on Freenode.

To change the source package that this bug is filed about visit https://bugs.launchpad.net/ubuntu/+bug/1516216/+editstatus and add the package name in the text box next to the word Package.

[This is an automated message. I apologize if it reached you inappropriately; please just reply to this message indicating so.]

[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 1516216

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.

[Mail-fabian-keller (mail-fabian-keller)]

apport information

[Mail-fabian-keller (mail-fabian-keller)]

apport information

[Mail-fabian-keller (mail-fabian-keller)]

apport information

[Mail-fabian-keller (mail-fabian-keller)]

apport information

[Mail-fabian-keller (mail-fabian-keller)]

apport information

[Mail-fabian-keller (mail-fabian-keller)]

apport information

[Mail-fabian-keller (mail-fabian-keller)]

apport information

[Mail-fabian-keller (mail-fabian-keller)]

apport information

[Mail-fabian-keller (mail-fabian-keller)]

apport information

[Mail-fabian-keller (mail-fabian-keller)]

apport information

[Mail-fabian-keller (mail-fabian-keller)]

apport information

[Mail-fabian-keller (mail-fabian-keller)]

apport information

[Mail-fabian-keller (mail-fabian-keller)]

apport information

[Mail-fabian-keller (mail-fabian-keller)]

apport information

[Mail-fabian-keller (mail-fabian-keller)]

The work-around I mentioned above (booting recovery + continue) does not seem to work reliably. It just took me half an hour to have a successful boot, to provide the apport-collect. A few more observations:

- For some reason my xorg.conf had been renamed to xorg.conf.11142015, without any xorg.conf in place. Apparently this must have happened yesterday, when my previous work around stopped working. I had the successful boot after renaming it back, but right now I don't dare to try out if this works systematically.
- Using kernel version 3.13.0-63 and earlier, X starts successfully and I end up with the default display manager. However, trying to log in results in an infinite loop of restarting the display manager. Furthermore, there seems to be a graphics issue: Even though the resolution seems to be standard 1080p, the image does not fill the entire screen area and sometimes the output is totally broken (very large stretch vertically, i.e., streching about 100 pixels over the entire screen plus strange color artifacts)

[Mail-fabian-keller (mail-fabian-keller)]

Just to confirm: The problem still exists with the newly released 352.63 version. I still get a black screen with this error:

Nov 21 18:23:51 fabuntu kernel: [ 1.366837] BUG: unable to handle kernel NULL pointer dereference at (null)
Nov 21 18:23:51 fabuntu kernel: [ 1.367022] IP: [<ffffffff8172a96b>] __down_common+0x4c/0x144

[...]

Nov 21 18:23:51 fabuntu kernel: [ 1.373666] Call Trace:
Nov 21 18:23:51 fabuntu kernel: [ 1.373757] [<ffffffff8172aa80>] __down+0x1d/0x1f
Nov 21 18:23:51 fabuntu kernel: [ 1.373846] [<ffffffff810b0f71>] down+0x41/0x50
Nov 21 18:23:51 fabuntu kernel: [ 1.373995] [<ffffffffa073d2e7>] nvidia_open+0x387/0x960 [nvidia]
Nov 21 18:23:51 fabuntu kernel: [ 1.374120] [<ffffffffa073c0c9>] nvidia_frontend_open+0x49/0xa0 [nvidia]
Nov 21 18:23:51 fabuntu kernel: [ 1.374217] [<ffffffff811c2d4f>] chrdev_open+0x9f/0x1d0
Nov 21 18:23:51 fabuntu kernel: [ 1.374313] [<ffffffff811bb883>] do_dentry_open+0x233/0x2e0
Nov 21 18:23:51 fabuntu kernel: [ 1.374404] [<ffffffff811c2cb0>] ? cdev_put+0x30/0x30
Nov 21 18:23:51 fabuntu kernel: [ 1.374497] [<ffffffff811bbbb9>] vfs_open+0x49/0x50
Nov 21 18:23:51 fabuntu kernel: [ 1.374590] [<ffffffff811cacf1>] do_last+0x541/0x1230
Nov 21 18:23:51 fabuntu kernel: [ 1.374690] [<ffffffff813161bb>] ? apparmor_file_alloc_security+0x5b/0x180
Nov 21 18:23:51 fabuntu kernel: [ 1.374783] [<ffffffff811cdd0b>] path_openat+0xbb/0x670
Nov 21 18:23:51 fabuntu kernel: [ 1.374875] [<ffffffff811cf12a>] do_filp_open+0x3a/0x90
Nov 21 18:23:51 fabuntu kernel: [ 1.374967] [<ffffffff811dbfd7>] ? __alloc_fd+0xa7/0x130
Nov 21 18:23:51 fabuntu kernel: [ 1.375060] [<ffffffff811bd6d9>] do_sys_open+0x129/0x280
Nov 21 18:23:51 fabuntu kernel: [ 1.375153] [<ffffffff811bd84e>] SyS_open+0x1e/0x20
Nov 21 18:23:51 fabuntu kernel: [ 1.375246] [<ffffffff81734cdd>] system_call_fastpath+0x1a/0x1f

[Graham Inggs (ginggs)]

I am seeing the same 'unable to handle kernel NULL pointer dereference' in comment #19 after running 'apt-get dist-upgrade' and not being online for several months.

Ubuntu 14.04, nvidia 340.96-0ubuntu0.14.04.1, kernels 3.13.0-49 and 3.13.0-74.
Intel motherboard with on-board graphics and Nvidia GTX 465 card.

After booting up once with 3.13.0.-74 normally, every time thereafter it briefly flashed the kernel Oops message and then switched to a black screen. I was later able to recover the full message from /var/log/kern.log.

Booting up with the 3.13.0-49 kernel gives me a low resolution X login screen, but a few seconds after logging in, the login screen appears again. The same as in comment #18.

A work-around is to boot up with the older kernel and then press Ctrl-Alt-F1 to switch to tty1, log in, and then 'sudo apt-get install --reinstall nvidia-340', or nvidia-352, etc. as desired.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.