There are over 400 changes to i915 between Ubuntu-4.3.0-7.18 and Ubuntu-4.4.0-2.16. We should probably narrow down the exact kernel version that introduced this first. At the same time, we can see if this is Ubuntu specific, so testing the upstream kernels is best.
We need to identify the earliest kernel that did not exhibit the bug and the first kernel that did exhibit the bug. Can you test the following kernels and post back? v4.4 final: http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.4-wily/ If v4.4 final exhibits the bug, we should move on to testing some of the v4.4 release candidates. v4.4-rc4: http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.4-rc4-wily/ If v4.4-rc4 does not exhibit the bug then test v4.4-rc6: v4.4-rc6: http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.4-rc6-wily/ If v4.4-rc4 does exhibit the bug then test v4.4-rc2: v4.4-rc2: http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.4-rc2-wily/ -- 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/1543683 Title: Fails to detect (second) display Status in linux package in Ubuntu: Confirmed Status in linux source package in Xenial: Confirmed Bug description: With the upgrade to 4.4.0-2, only one of the two displays in the machine is detected. With 4.3.0-7 (and earlier) both are detected. In this case, both display connectors are on the MB. ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: linux-image-extra-4.4.0-2-generic 4.4.0-2.16 ProcVersionSignature: Ubuntu 4.4.0-2.16-generic 4.4.0 Uname: Linux 4.4.0-2-generic x86_64 ApportVersion: 2.19.4-0ubuntu2 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC0: lamont 3923 F.... pulseaudio CurrentDesktop: Unity Date: Tue Feb 9 10:22:38 2016 HibernationDevice: RESUME=UUID=5d145c55-633f-4197-a4c9-0b165b6dbeb3 InstallationDate: Installed on 2014-09-22 (505 days ago) InstallationMedia: Ubuntu-Server 14.04 LTS "Trusty Tahr" - Release amd64 (20140416.2) MachineType: Shuttle Inc SG41 ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.0-2-generic root=UUID=ba0ea95b-cde0-42ba-b06e-9fd6ca006881 ro nomdmonddf nomdmonisw RelatedPackageVersions: linux-restricted-modules-4.4.0-2-generic N/A linux-backports-modules-4.4.0-2-generic N/A linux-firmware 1.155 RfKill: 0: hci0: Bluetooth Soft blocked: no Hard blocked: no SourcePackage: linux UpgradeStatus: Upgraded to xenial on 2014-11-14 (452 days ago) dmi.bios.date: 02/10/2011 dmi.bios.vendor: American Megatrends Inc. dmi.bios.version: 080015 dmi.board.asset.tag: To Be Filled By O.E.M. dmi.board.name: FG41 dmi.board.vendor: Shuttle Inc dmi.board.version: V20 dmi.chassis.asset.tag: To Be Filled By O.E.M. dmi.chassis.type: 3 dmi.chassis.vendor: Shuttle Inc dmi.chassis.version: To Be Filled By O.E.M. dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr080015:bd02/10/2011:svnShuttleInc:pnSG41:pvrV20:rvnShuttleInc:rnFG41:rvrV20:cvnShuttleInc:ct3:cvrToBeFilledByO.E.M.: dmi.product.name: SG41 dmi.product.version: V20 dmi.sys.vendor: Shuttle Inc To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1543683/+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
