← Back to team overview

kernel-packages team mailing list archive

[Bug 1585081] Re: Switching user freezes system


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
v4.6 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:

Once testing of the upstream kernel is complete, please mark this bug as

Thanks in advance.

[0] http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.6-yakkety

** Changed in: linux (Ubuntu)
   Importance: Undecided => High

** Changed in: linux (Ubuntu)
       Status: Confirmed => Incomplete

You received this bug notification because you are a member of Kernel
Packages, which is subscribed to linux in Ubuntu.

  Switching user freezes system

Status in linux package in Ubuntu:

Bug description:
  Just doing this my system freezes:

  1. Click on the top right gear icon.
  2. Select a different user account.

  Login screen appears briefly, then black screen and the system is

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000248
  IP: [<ffffffffc0258eb2>] amdgpu_vm_grab_id+0x122/0x310 [amdgpu]
  PGD 0
  Oops: 0000 [#1] SMP
  Modules linked in:  ...
  (See attached syslog for more)

  ProblemType: Bug
  DistroRelease: Ubuntu 16.04
  Package: linux-image-4.4.0-22-generic 4.4.0-22.40
  ProcVersionSignature: Ubuntu 4.4.0-22.40-generic 4.4.8
  Uname: Linux 4.4.0-22-generic x86_64
  ApportVersion: 2.20.1-0ubuntu2
  Architecture: amd64
   /dev/snd/controlC0:  david      2739 F.... pulseaudio
   /dev/snd/controlC1:  david      2739 F.... pulseaudio
  CurrentDesktop: Unity
  Date: Tue May 24 08:54:13 2016
  HibernationDevice: RESUME=UUID=d225720a-fc40-49a3-9182-17d278d40460
  InstallationDate: Installed on 2015-06-29 (329 days ago)
  InstallationMedia: Ubuntu 15.04 "Vivid Vervet" - Release amd64 (20150422)
  ProcFB: 0 inteldrmfb
  ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-4.4.0-22-generic.efi.signed root=/dev/mapper/ubuntu--vg-root ro quiet splash vt.handoff=7
   linux-restricted-modules-4.4.0-22-generic N/A
   linux-backports-modules-4.4.0-22-generic  N/A
   linux-firmware                            1.157
  SourcePackage: linux
  UpgradeStatus: Upgraded to xenial on 2016-04-22 (31 days ago)
  dmi.bios.date: 12/02/2014
  dmi.bios.vendor: INSYDE Corp.
  dmi.bios.version: 2.00
  dmi.board.asset.tag: Type2 - Board Asset Tag
  dmi.board.name: Type2 - Board Product Name1
  dmi.board.vendor: Type2 - Board Vendor Name1
  dmi.board.version: Type2 - Board Version
  dmi.chassis.asset.tag: No Asset Tag
  dmi.chassis.type: 10
  dmi.chassis.vendor: OEM Chassis ManuFacturer
  dmi.chassis.version: OEM Chassis Version
  dmi.modalias: dmi:bvnINSYDECorp.:bvr2.00:bd12/02/2014:svnTOSHIBA:pnSATELLITES50-B:pvrPSPQEE-00F00JEN:rvnType2-BoardVendorName1:rnType2-BoardProductName1:rvrType2-BoardVersion:cvnOEMChassisManuFacturer:ct10:cvrOEMChassisVersion:
  dmi.product.name: SATELLITE S50-B
  dmi.product.version: PSPQEE-00F00JEN
  dmi.sys.vendor: TOSHIBA

To manage notifications about this bug go to: