amdgpu.dc fails on AMD (Kaveri) A10-7300

[semreh]

Booting kernel 4.16 ( BOOT_IMAGE=/vmlinuz-4.16.0-041600-generic ) with external monitor attached to VGA port of Lenovo Ideapad Z50-75 (AMD Kaveri A10-7300) results in blank external display when amdgpu.ci_support is forced (i.e. radeon disabled).

key dmesg messages are:

[ 1.897177] [drm:construct [amdgpu]] *ERROR* construct: Invalid Connector ObjectID from Adapter Service for connector index:3! type 0 expected 3
[ 1.897266] [drm:construct [amdgpu]] *ERROR* construct: Invalid Connector ObjectID from Adapter Service for connector index:4! type 0 expected 3
[ 1.897380] [drm:construct [amdgpu]] *ERROR* construct: Invalid Connector ObjectID from Adapter Service for connector index:5! type 0 expected 3
[ 1.897489] [drm:construct [amdgpu]] *ERROR* construct: Invalid Connector ObjectID from Adapter Service for connector index:6! type 0 expected 3

Kernel boot options are: amdgpu.cik_support=1 radeon.cik_support=0

If I boot the same kernel with the following options:

amdgpu.cik_support=1 radeon.cik_support=0 amdgpu.dc=0

The VGA attached display works.

Attached in the tar are:

version.log - output of cat /proc/version
lspci-vnvn.log - output of sudo lscpi -vnvn
dmesg_amdgpu.dc-(default-one) - dmesg from boot with amdgpu.cik_support forced and amdgpu.dc left to deafult
dmesg_amdgpu.dc-0 - dmesg from boot with amdgpu.cik_support forced and amdgpu.dc disabled
---
ApportVersion: 2.20.1-0ubuntu2.15
Architecture: amd64
CurrentDesktop: LXDE
DistroRelease: Ubuntu 16.04
InstallationDate: Installed on 2017-09-05 (213 days ago)
InstallationMedia: Lubuntu 16.04.3 LTS "Xenial Xerus" - Release amd64 (20170801)
JournalErrors:
 Error: command ['journalctl', '-b', '--priority=warning', '--lines=1000'] failed with exit code 1: Failed to search journal ACL: Operation not supported
 No journal files were opened due to insufficient permissions.
Package: linux (not installed)
Tags: xenial
Uname: Linux 4.16.0-041600-generic x86_64
UnreportableReason: The running kernel is not an Ubuntu kernel
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip kismet libvirtd lpadmin plugdev sambashare scanner sudo
_MarkForUpload: True

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

This bug is missing log files that will aid in diagnosing the problem. While running an Ubuntu kernel (not a mainline or third-party kernel) please enter the following command in a terminal window:

apport-collect 1761825

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.

[semreh (launchpad-via-forwarder)]

apport information

[semreh (launchpad-via-forwarder)]

apport information

[Joseph Salisbury (jsalisbury)]

Would it be possible for you to test the latest upstream kernel? Refer to https://wiki.ubuntu.com/KernelMainlineBuilds . Please test the latest v4.16 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/v4.16

[semreh (launchpad-via-forwarder)]

Tested on 4.16.8-041608-generic, and issue remains.

See https://bugs.launchpad.net/ubuntu/bionic/+source/linux/+bug/1761751

[Launchpad Janitor (janitor)]

[Expired for linux (Ubuntu) because there has been no activity for 60 days.]