[Radeon HD 8830M / R7 465X] *ERROR* atombios stuck in loop for more than 5secs aborting

[Maxime Accadia]

Ubuntu 18.04 freezes on every startup after GDM. This happens with DELL Optiplex 7450 All In One with both an Intel graphics chipset and an AMD Graphic card.

I have tested with kernels 4.15.0-29, 4.15.0-64 and latest HWE kernel (5.0.0-29) ; all are affected.

As a workaround, it's possible to disabled the radeon card with modprobe.blacklist=radeon kernel parameter.

I tried to dump the video bios rom (https://dri.freedesktop.org/wiki/TestingAndDebugging/) without success.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: linux-image-4.15.0-64-generic 4.15.0-64.73
ProcVersionSignature: Ubuntu 4.15.0-64.73-generic 4.15.18
Uname: Linux 4.15.0-64-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.7
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: admin-crip 1729 F.... pulseaudio
Date: Wed Sep 18 13:08:44 2019
InstallationDate: Installed on 2019-09-18 (0 days ago)
InstallationMedia: Ubuntu 18.04.1 LTS "Bionic Beaver" - Release amd64 (20180725)
IwConfig:
 lo no wireless extensions.

 enp0s31f6 no wireless extensions.
Lsusb:
 Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
 Bus 001 Device 003: ID 413c:301a Dell Computer Corp.
 Bus 001 Device 002: ID 413c:2113 Dell Computer Corp.
 Bus 001 Device 004: ID 1bcf:2b94 Sunplus Innovation Technology Inc.
 Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
MachineType: Dell Inc. OptiPlex 7450 AIO
ProcEnviron:
 TERM=linux
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=fr_FR.UTF-8
 SHELL=/bin/bash
ProcFB: 0 inteldrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.15.0-64-generic root=UUID=e9dc513b-7fb2-45b4-8843-104558e9056b ro
RelatedPackageVersions:
 linux-restricted-modules-4.15.0-64-generic N/A
 linux-backports-modules-4.15.0-64-generic N/A
 linux-firmware 1.173.9
RfKill:

SourcePackage: linux
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 05/13/2019
dmi.bios.vendor: Dell Inc.
dmi.bios.version: 1.13.1
dmi.board.name: 019KMN
dmi.board.vendor: Dell Inc.
dmi.board.version: A01
dmi.chassis.type: 13
dmi.chassis.vendor: Dell Inc.
dmi.modalias: dmi:bvnDellInc.:bvr1.13.1:bd05/13/2019:svnDellInc.:pnOptiPlex7450AIO:pvr:rvnDellInc.:rn019KMN:rvrA01:cvnDellInc.:ct13:cvr:
dmi.product.family: OptiPlex
dmi.product.name: OptiPlex 7450 AIO
dmi.sys.vendor: Dell Inc.

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This change was made by a bot.

[Maxime Accadia (maxacc)]

I did some more testing. All fresh installations with updates.

Not affected :
 * 16.04 with kernel 4.4.0-164
 * 16.04 with kernel 4.4.0-161
 * 16.04 with kernel 4.4.0-159
 * 16.04 with kernel 4.4.0-157

Affected :
 * 16.04 with kernel 4.15.0-64 (HWE)
 * 18.04 with kernel 4.15.0-29
 * 18.04 with kernel 4.15.0-64
 * 18.04 with kernel 5.0.0-29 (HWE)
 * 19.04 with kernel 5.0.0-29