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. ** Changed in: linux (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1761825 Title: amdgpu.dc fails on AMD (Kaveri) A10-7300 Status in linux package in Ubuntu: Incomplete Bug description: 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 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1761825/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp