My system intermittently locks up every few days. It does not seem to correspond to a particular program or action. When that happens, the screen goes to black, then returns after a few seconds. At that point, the time on the clock is static and indicates that the screen is frozen, but audio continues to play for 30 seconds to a minute. The keyboard and mouse do not affect what's being displayed, but I can Alt - SysRq - REISUB to restart.

Every time (12 crashes and counting), /var/log/kern.log indicates that

kernel: [353692.378886] radeon 0000:03:00.0: ring 0 stalled for more than 10280msec
kernel: [353692.378896] radeon 0000:03:00.0: GPU lockup (current fence id 0x00000000006e96e5 last fence id 0x00000000006e96e9 on ring 0)

just before the system locks. Different ring numbers are reported as stalling at different times.

I am posting at bugs.freedesktop.org at the suggestion of a poster from bugs.lauchpad.net.  For additional info, see:

https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1707695



I'm running 16.04 LTS.
:~$ lsb_release -rd
Description: Ubuntu 16.04.2 LTS
Release: 16.04

According to the Software Center, I am running Ubuntu Software 3.20.1.

I have a Radeon HD graphics card.

:~$ lspci | grep VGA
03:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Cedar [Radeon HD 5000/6000/7350/8350 Series]

:~$ lspci -v -s 03:00.0
03:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Cedar [Radeon HD 5000/6000/7350/8350 Series] (prog-if 00 [VGA controller])
Subsystem: Gigabyte Technology Co., Ltd Cedar [Radeon HD 5000/6000/7350/8350 Series]
Flags: bus master, fast devsel, latency 0, IRQ 53
Memory at c0000000 (64-bit, prefetchable) [size=256M]
Memory at d3d20000 (64-bit, non-prefetchable) [size=128K]
I/O ports at 7000 [size=256]
Expansion ROM at d3d00000 [disabled] [size=128K]
Capabilities: <access denied>
Kernel driver in use: radeon
Kernel modules: radeon

Please let me know if additional information would be useful, and I will be glad to provide it. Thanks in advance.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: linux-image-4.4.0-87-generic 4.4.0-87.110
ProcVersionSignature: Ubuntu 4.4.0-87.110-generic 4.4.73
Uname: Linux 4.4.0-87-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.10
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: clapp 3889 F.... pulseaudio
 /dev/snd/controlC2: clapp 3889 F.... pulseaudio
 /dev/snd/controlC1: clapp 3889 F.... pulseaudio
CurrentDesktop: Unity
Date: Mon Jul 31 14:02:27 2017
HibernationDevice: RESUME=UUID=1b30dad6-8c48-42cf-ae26-66ab8b0eb446
InstallationDate: Installed on 2013-09-04 (1425 days ago)
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release amd64 (20111012)
MachineType: Dell Inc. Precision T7600
ProcFB: 0 radeondrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.0-87-generic root=UUID=33722f76-37fd-4289-b071-d7f48b65dd32 ro quiet splash crashkernel=384M-:128M vt.handoff=7
RelatedPackageVersions:
 linux-restricted-modules-4.4.0-87-generic N/A
 linux-backports-modules-4.4.0-87-generic N/A
 linux-firmware 1.157.11
RfKill:
 0: hci0: Bluetooth
  Soft blocked: no
  Hard blocked: no
SourcePackage: linux
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 05/03/2013
dmi.bios.vendor: Dell Inc.
dmi.bios.version: A07
dmi.board.name: 082WXT
dmi.board.vendor: Dell Inc.
dmi.board.version: A01
dmi.chassis.type: 7
dmi.chassis.vendor: Dell Inc.
dmi.modalias: dmi:bvnDellInc.:bvrA07:bd05/03/2013:svnDellInc.:pnPrecisionT7600:pvr01:rvnDellInc.:rn082WXT:rvrA01:cvnDellInc.:ct7:cvr:
dmi.product.name: Precision T7600
dmi.product.version: 01
dmi.sys.vendor: Dell Inc.

From https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1707695 , what would be an workaround until this bug is fixed for Ubuntu 18.10 / kernel 4.18.0-10-generic ?

Perhaps also link related bugs from https://bugs.freedesktop.org/buglist.cgi?bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED&list_id=659728&query_format=advanced&short_desc=radeon%20ring%20stalled%20&short_desc_type=allwordssubstr

Christopher, are you still experiencing this bug?

(In reply to Pander from comment #3)
> Christopher, are you still experiencing this bug?

Pander, the Radeon graphics card in my computer died, so I replaced it with an Nvidia card.  I didn't experience the bug again after that.

Resolving per comment 4, thanks for the report and follow-ups.