Submitted: https://bugs.freedesktop.org/show_bug.cgi?id=106529
** Bug watch added: freedesktop.org Bugzilla #106529 https://bugs.freedesktop.org/show_bug.cgi?id=106529 -- 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/1770836 Title: amdgpu+xorg possibly marks displays as off while they wake from sleep Status in linux package in Ubuntu: Confirmed Bug description: Ubuntu 18.04, all the x, libdrm, kernel, etc. packages up to date. KDE. When waking the displays from sleep with 4.15 any display not yet fully woken up seem to be reported as disconnected. This happens both when waking the whole computer from sleep (systemctl suspend) or just the displays themselves (due to me not touching mouse+keyboard for a while). Setup: Radeon RX 560 Primary display: bottom right, displayport, on Secondary display 1: left, hdmi, on Secondary display 2: top right, dvi, off Video of how it should work, using 4.4.15: https://www.youtube.com/watch?v=h7nMYbm5ZxU Note how even though the left (secondary) display wakes up first, both instantly display their proper desktops. Video of how it works with the current default kernel (and 4.16.7 from kernel-ppa/mainline): https://www.youtube.com/watch?v=VdVFNXPszSI Note how when the left (secondary) display wakes up first, KDE decides that this is probably the only display available, so tries to switch the primary desktop to it, then a split second later the bottom right wakes up and KDE knows *that* should be the primary according to the config, so it switches back. My interpretation is that KDE thinks the bottom right display slowly waking up is actually off, so it does the reasonable thing and uses the other available one as primary. One way or the other, that's not how it used to work in older kernels, so as far as I'm concerned it's a regression. --- ApportVersion: 2.20.9-0ubuntu7 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC0: mmazur 2270 F.... pulseaudio /dev/snd/controlC1: mmazur 2270 F.... pulseaudio CurrentDesktop: KDE DistroRelease: Ubuntu 18.04 MachineType: To Be Filled By O.E.M. To Be Filled By O.E.M. Package: linux (not installed) ProcFB: 0 amdgpudrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.15.0-20-generic root=UUID=d170afa1-e8de-4480-a0d7-4a4e8e304caf ro amdgpu.dc_log=1 ProcVersionSignature: Ubuntu 4.15.0-20.21-generic 4.15.17 RelatedPackageVersions: linux-restricted-modules-4.15.0-20-generic N/A linux-backports-modules-4.15.0-20-generic N/A linux-firmware 1.173 RfKill: 1: hci0: Bluetooth Soft blocked: no Hard blocked: no Tags: bionic Uname: Linux 4.15.0-20-generic x86_64 UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: adm bacula cdrom dip docker libvirt libvirtd lpadmin plugdev sambashare sudo _MarkForUpload: True dmi.bios.date: 04/29/2016 dmi.bios.vendor: American Megatrends Inc. dmi.bios.version: P2.10 dmi.board.name: Z97E-ITX/ac dmi.board.vendor: ASRock dmi.chassis.asset.tag: To Be Filled By O.E.M. dmi.chassis.type: 3 dmi.chassis.vendor: To Be Filled By O.E.M. dmi.chassis.version: To Be Filled By O.E.M. dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrP2.10:bd04/29/2016:svnToBeFilledByO.E.M.:pnToBeFilledByO.E.M.:pvrToBeFilledByO.E.M.:rvnASRock:rnZ97E-ITX/ac:rvr:cvnToBeFilledByO.E.M.:ct3:cvrToBeFilledByO.E.M.: dmi.product.family: To Be Filled By O.E.M. dmi.product.name: To Be Filled By O.E.M. dmi.product.version: To Be Filled By O.E.M. dmi.sys.vendor: To Be Filled By O.E.M. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1770836/+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