Public bug reported:
After upgrading to Ubuntu 18.04 (and thus from Linux 4.13 to Linux 4.15)
the Monitor connected via VGA (through DVI-I) shows a 'No Signal'
message after amdgpu takes over from efifb and turns off.
The monitor worked fine in Ubuntu 17.10 and Linux 4.13.
When looking at the output of xrandr, the analog monitor is now detected
as DVI-D instead of DVI-I and thus probably won't receive an analog
signal anymore.
After some investigation, it turns out the monitor will light up when
adding the `amdgpu.dc=0` kernel parameter.
I've tried Linux 4.18-rc6 from the mainline ppa and the issue persists
unless I add the kernel parameter to disable DC.
ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: linux-image-generic 4.15.0.29.31
ProcVersionSignature: Ubuntu 4.15.0-29.31-generic 4.15.18
Uname: Linux 4.15.0-29-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.2
Architecture: amd64
AudioDevicesInUse:
USER PID ACCESS COMMAND
/dev/snd/pcmC0D0p: benpicco 2151 F...m pulseaudio
/dev/snd/controlC0: benpicco 2151 F.... pulseaudio
/dev/snd/controlC1: benpicco 2151 F.... pulseaudio
CurrentDesktop: MATE
Date: Sat Jul 28 17:55:35 2018
EcryptfsInUse: Yes
HibernationDevice: RESUME=UUID=ef400a46-b237-4272-b4a7-f866e92d00a0
InstallationDate: Installed on 2016-08-06 (720 days ago)
InstallationMedia: Ubuntu 16.04.1 LTS "Xenial Xerus" - Release amd64 (20160719)
IwConfig:
lo no wireless extensions.
eno1 no wireless extensions.
MachineType: System manufacturer System Product Name
ProcFB: 0 amdgpudrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.15.0-29-generic
root=UUID=8e6b0d6a-eb87-44cf-8fc3-b13bd97b71d2 ro amdgpu.dc=0
RelatedPackageVersions:
linux-restricted-modules-4.15.0-29-generic N/A
linux-backports-modules-4.15.0-29-generic N/A
linux-firmware 1.173.1
RfKill:
0: hci0: Bluetooth
Soft blocked: no
Hard blocked: no
SourcePackage: linux
UpgradeStatus: Upgraded to bionic on 2018-07-28 (0 days ago)
dmi.bios.date: 11/09/2012
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: 3603
dmi.board.asset.tag: To be filled by O.E.M.
dmi.board.name: P8Z68-V
dmi.board.vendor: ASUSTeK Computer INC.
dmi.board.version: Rev 1.xx
dmi.chassis.asset.tag: Asset-1234567890
dmi.chassis.type: 3
dmi.chassis.vendor: Chassis Manufacture
dmi.chassis.version: Chassis Version
dmi.modalias:
dmi:bvnAmericanMegatrendsInc.:bvr3603:bd11/09/2012:svnSystemmanufacturer:pnSystemProductName:pvrSystemVersion:rvnASUSTeKComputerINC.:rnP8Z68-V:rvrRev1.xx:cvnChassisManufacture:ct3:cvrChassisVersion:
dmi.product.family: To be filled by O.E.M.
dmi.product.name: System Product Name
dmi.product.version: System Version
dmi.sys.vendor: System manufacturer
** Affects: linux (Ubuntu)
Importance: Undecided
Status: Confirmed
** Tags: amd64 apport-bug bionic
--
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.
https://bugs.launchpad.net/bugs/1784156
Title:
[regression][amdgpu] analog outputs stop working after upgrading to
Ubuntu 18.04
To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1784156/+subscriptions
--
ubuntu-bugs mailing list
ubuntu-bugs@lists.ubuntu.com
https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
