Public bug reported: After updating the HWE stack on Ubuntu 14.04 LTS, my computer now regularly boots to a black screen upon startup. I briefly see the purple screen (but no plymouth), and then nothing. You can hear the ubuntu drum roll, though, and I can reboot using the alt+Sysrq+B option.
Adding the nomodeset parameter in GRUB offers a solution of sorts, but the computer boots with Gallium 0.4 on llvmpipe graphics, which makes gaming basically impossible. I can still boot regularly using the 3.16.0-77-generic kernel saved in GRUB. Other info: 1) I tried an Ubuntu live USB stick with both 14.04.5 on it and then 16.04 and got the same problem. 2) My UEFI firmware is up-to-date as of 1 or 2 days ago. 3) The kernel in question is 4.4.0-36-generic. 4) Ubuntu release: 14.04.5 LTS 5) I have never installed the fglrx driver—I have always used the open-source driver. 6) My exact GPU: AMD A10-7700K Radeon R7 (Kaveri). 7) I'm not sure that the dmesg log automatically attached by apport will be helpful because of the "nomodeset" parameter, so I have attached a dmesg log grabbed from a failed boot. With guidance, I can do the same for other relevant logs. Hope that's helpful! ProblemType: Bug DistroRelease: Ubuntu 14.04 Package: xorg 1:7.7+1ubuntu8.1 ProcVersionSignature: Ubuntu 4.4.0-36.55~14.04.1-generic 4.4.16 Uname: Linux 4.4.0-36-generic x86_64 .tmp.unity.support.test.1: ApportVersion: 2.14.1-0ubuntu3.21 Architecture: amd64 CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins' CompositorRunning: compiz CompositorUnredirectDriverBlacklist: '(nouveau|Intel).*Mesa 8.0' CompositorUnredirectFSW: true CurrentDesktop: Unity Date: Tue Sep 13 21:46:45 2016 DistUpgraded: 2016-08-26 20:07:12,800 DEBUG enabling apt cron job DistroCodename: trusty DistroVariant: ubuntu ExtraDebuggingInterest: Yes, if not too technical GraphicsCard: Advanced Micro Devices, Inc. [AMD/ATI] Kaveri [Radeon R7 Graphics] [1002:1313] (prog-if 00 [VGA controller]) Subsystem: ASRock Incorporation Device [1849:1313] InstallationDate: Installed on 2015-06-24 (447 days ago) InstallationMedia: Ubuntu 14.04.2 LTS "Trusty Tahr" - Release amd64 (20150218.1) MachineType: To Be Filled By O.E.M. To Be Filled By O.E.M. ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.0-36-generic root=UUID=228ea1db-87eb-476d-b97f-5a4a28c618f4 ro nomodeset quiet splash vt.handoff=7 Renderer: Software SourcePackage: xorg UpgradeStatus: Upgraded to trusty on 2016-08-27 (18 days ago) dmi.bios.date: 03/15/2016 dmi.bios.vendor: American Megatrends Inc. dmi.bios.version: P2.30 dmi.board.name: FM2A78M-HD+ R2.0 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.:bvrP2.30:bd03/15/2016:svnToBeFilledByO.E.M.:pnToBeFilledByO.E.M.:pvrToBeFilledByO.E.M.:rvnASRock:rnFM2A78M-HD+R2.0:rvr:cvnToBeFilledByO.E.M.:ct3:cvrToBeFilledByO.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. version.compiz: compiz 1:0.9.11.3+14.04.20160425-0ubuntu1 version.ia32-libs: ia32-libs N/A version.libdrm2: libdrm2 2.4.67-1ubuntu0.14.04.1 version.libgl1-mesa-dri: libgl1-mesa-dri N/A version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A version.libgl1-mesa-glx: libgl1-mesa-glx N/A version.xserver-xorg-core: xserver-xorg-core N/A version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A version.xserver-xorg-video-ati: xserver-xorg-video-ati N/A version.xserver-xorg-video-intel: xserver-xorg-video-intel N/A version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau N/A xserver.bootTime: Tue Sep 13 21:07:07 2016 xserver.configfile: default xserver.errors: open /dev/dri/card0: No such file or directory open /dev/dri/card0: No such file or directory Screen 0 deleted because of no matching config section. Screen 0 deleted because of no matching config section. AIGLX: reverting to software rendering xserver.logfile: /var/log/Xorg.0.log xserver.outputs: xserver.version: 2:1.18.3-1ubuntu2.2~trusty3 ** Affects: xorg (Ubuntu) Importance: Undecided Status: New ** Tags: amd64 apport-bug compiz-0.9 trusty ubuntu ** Attachment added: "Dmesg log from failed boot WITHOUT nomodeset parameter" https://bugs.launchpad.net/bugs/1623295/+attachment/4740482/+files/dmesg.0 -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xorg in Ubuntu. https://bugs.launchpad.net/bugs/1623295 Title: Black screen on startup after HWE stack update on Ubuntu 14.04 LTS [Radeon R7 graphics] To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1623295/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp