Étienne BERSAC, thank you for reporting this and helping make Ubuntu better. Could you please test the latest upstream kernel available from the very top line at the top of the page (the release names are irrelevant for testing, and please do not test the daily folder) following https://wiki.ubuntu.com/KernelMainlineBuilds ? It will allow additional upstream developers to examine the issue.
If the test did not allow you to test to the issue (ex. you couldn't boot into the OS) please make a comment in your report about this, and continue to test the next most recent kernel version until you can test to the issue. Once you've tested the upstream kernel, please comment on which kernel version specifically you tested. If this bug is fixed in the mainline kernel, please add the following tags by clicking on the yellow circle with a black pencil icon, next to the word Tags, located at the bottom of the report description: kernel-fixed-upstream kernel-fixed-upstream-X.Y-rcZ Where XY and Z are numbers corresponding to the kernel version. If the mainline kernel does not fix this bug, please add the following tags: kernel-bug-exists-upstream kernel-bug-exists-upstream-X.Y-rcZ Once testing of the upstream kernel is complete, please mark this bug's Status as Confirmed. Please let us know your results. ** Tags added: latest-bios ** Changed in: linux (Ubuntu) Importance: Undecided => Medium ** Changed in: linux (Ubuntu) Status: Confirmed => 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/1452858 Title: Screen lit off on iMac 12,2 after a while Status in linux package in Ubuntu: Incomplete Bug description: Hello, I'm running Ubuntu on an iMac 12,2 since november 2012. From time to time and more and more frequently the screen lit off. The only way i can get it on is to suspend/resume. But then, it lit off soon. I suspect some heating. Actually, the output of the cooling system is way hotter with Ubuntu than Mac OS X. So i would like to switch to the IGD card rather than the discrete one. But there is no vga_switcheroo. How to debug screen lit off ? How to detect screen heating ? How to disable discrete card ? Is it kernel ? Xorg ? Where to search ? Regards, Étienne ProblemType: Bug DistroRelease: Ubuntu 15.04 Package: linux-image-3.19.0-15-generic 3.19.0-15.15 [modified: boot/vmlinuz-3.19.0-15-generic] ProcVersionSignature: Ubuntu 3.19.0-15.15-generic 3.19.3 Uname: Linux 3.19.0-15-generic x86_64 ApportVersion: 2.17.2-0ubuntu1 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC1: bersace 1709 F.... pulseaudio gdm 28946 F.... pulseaudio /dev/snd/controlC0: bersace 1709 F.... pulseaudio gdm 28946 F.... pulseaudio CRDA: country AW: DFS-UNSET (2402 - 2482 @ 40), (N/A, 20), (N/A) (5170 - 5250 @ 40), (N/A, 20), (N/A) (5250 - 5330 @ 40), (N/A, 20), (0 ms), DFS (5490 - 5710 @ 40), (N/A, 27), (0 ms), DFS Date: Thu May 7 20:51:33 2015 HibernationDevice: RESUME=UUID=a842b955-b20e-4514-af83-7b6f45dc1000 InstallationDate: Installed on 2015-04-29 (8 days ago) InstallationMedia: Ubuntu-GNOME 15.04 "Vivid Vervet" - Release amd64 (20150422) MachineType: Apple Inc. iMac12,2 ProcEnviron: TERM=screen PATH=(custom, no user) LANG=fr_FR.UTF-8 SHELL=/bin/bash ProcFB: 0 inteldrmfb 1 radeondrmfb ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-3.19.0-15-generic.efi.signed root=UUID=6f639d83-47c9-41fb-aa9b-c3931e37acc5 ro rootflags=subvol=@ quiet splash vt.handoff=7 PulseList: Error: command ['pacmd', 'list'] failed with exit code 1: No PulseAudio daemon running, or not running as session daemon. RelatedPackageVersions: linux-restricted-modules-3.19.0-15-generic N/A linux-backports-modules-3.19.0-15-generic N/A linux-firmware 1.143 SourcePackage: linux UdevLog: Error: [Errno 2] No such file or directory: '/var/log/udev' UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 01/24/12 dmi.bios.vendor: Apple Inc. dmi.bios.version: IM121.88Z.0047.B1F.1201241648 dmi.board.name: Mac-942B59F58194171B dmi.board.vendor: Apple Inc. dmi.board.version: iMac12,2 dmi.chassis.type: 13 dmi.chassis.vendor: Apple Inc. dmi.chassis.version: Mac-942B59F58194171B dmi.modalias: dmi:bvnAppleInc.:bvrIM121.88Z.0047.B1F.1201241648:bd01/24/12:svnAppleInc.:pniMac12,2:pvr1.0:rvnAppleInc.:rnMac-942B59F58194171B:rvriMac12,2:cvnAppleInc.:ct13:cvrMac-942B59F58194171B: dmi.product.name: iMac12,2 dmi.product.version: 1.0 dmi.sys.vendor: Apple Inc. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1452858/+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