[amdgpu] Black screen after standby - clean Kubuntu on AMD T495

[snow]

I installed a fresh Kubuntu 20.04. on my Thinkpad T495 (AMD). No further software, simply clean installation. After every standby the Laptop wakes up, but shows only black screen. No way to get back to Kubuntu desktop.

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: xorg 1:7.7+19ubuntu14
ProcVersionSignature: Ubuntu 5.4.0-28.32-generic 5.4.30
Uname: Linux 5.4.0-28-generic x86_64
ApportVersion: 2.20.11-0ubuntu27
Architecture: amd64
BootLog: Error: [Errno 13] Keine Berechtigung: '/var/log/boot.log'
CasperMD5CheckResult: skip
CompositorRunning: None
CurrentDesktop: KDE
Date: Sat May 2 11:48:04 2020
DistUpgraded: Fresh install
DistroCodename: focal
DistroVariant: ubuntu
ExtraDebuggingInterest: I just need to know a workaround
GraphicsCard:
 Advanced Micro Devices, Inc. [AMD/ATI] Picasso [1002:15d8] (rev d2) (prog-if 00 [VGA controller])
   Subsystem: Lenovo Picasso [17aa:5125]
InstallationDate: Installed on 2020-05-01 (0 days ago)
InstallationMedia: Kubuntu 20.04 LTS "Focal Fossa" - Release amd64 (20200423)
MachineType: LENOVO 20NKS01Y00
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.4.0-28-generic root=UUID=537c947f-55fc-4bba-bb91-e7c4b91e39e6 ro quiet splash vt.handoff=7
SourcePackage: xorg
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 01/06/2020
dmi.bios.vendor: LENOVO
dmi.bios.version: R12ET49W(1.19 )
dmi.board.asset.tag: Not Available
dmi.board.name: 20NKS01Y00
dmi.board.vendor: LENOVO
dmi.board.version: Not Defined
dmi.chassis.asset.tag: No Asset Information
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: None
dmi.modalias: dmi:bvnLENOVO:bvrR12ET49W(1.19):bd01/06/2020:svnLENOVO:pn20NKS01Y00:pvrThinkPadT495:rvnLENOVO:rn20NKS01Y00:rvrNotDefined:cvnLENOVO:ct10:cvrNone:
dmi.product.family: ThinkPad T495
dmi.product.name: 20NKS01Y00
dmi.product.sku: LENOVO_MT_20NK_BU_Think_FM_ThinkPad T495
dmi.product.version: ThinkPad T495
dmi.sys.vendor: LENOVO
version.compiz: compiz N/A
version.libdrm2: libdrm2 2.4.101-2
version.libgl1-mesa-dri: libgl1-mesa-dri 20.0.4-2ubuntu1
version.libgl1-mesa-glx: libgl1-mesa-glx N/A
version.xserver-xorg-core: xserver-xorg-core 2:1.20.8-2ubuntu2
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:19.1.0-1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20200226-1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.16-1

[Daniel van Vugt (vanvugt)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. It sounds like some part of the system has crashed. To help us find the cause of the crash please follow these steps:

1. Look in /var/crash for crash files and if found run:
    ubuntu-bug YOURFILE.crash
Then tell us the ID of the newly-created bug.

2. If step 1 failed then look at https://errors.ubuntu.com/user/ID where ID is the content of file /var/lib/whoopsie/whoopsie-id on the machine. Do you find any links to recent problems on that page? If so then please send the links to us.

3. If step 2 also failed then apply the workaround from bug 994921, reboot, reproduce the crash, and retry step 1.

Please take care to avoid attaching .crash files to bugs as we are unable to process them as file attachments. It would also be a security risk for yourself.

[Launchpad Janitor (janitor)]

[Expired for xserver-xorg-video-amdgpu (Ubuntu) because there has been no activity for 60 days.]