Public bug reported: Booting a ThinkPad T420s with discrete graphics enabled in the causes a hang during the boot.
The hang happens somewhere during udev startup, I think. As described in #1007138, adding pci=noacpi to the kernel command line fixes the problem. ProblemType: Bug DistroRelease: Ubuntu 13.10 Package: linux-image-3.11.0-13-generic 3.11.0-13.20 ProcVersionSignature: Ubuntu 3.11.0-13.20-generic 3.11.6 Uname: Linux 3.11.0-13-generic x86_64 NonfreeKernelModules: nvidia ApportVersion: 2.12.5-0ubuntu2.1 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC1: olli 1732 F.... pulseaudio /dev/snd/controlC0: olli 1732 F.... pulseaudio /dev/snd/pcmC0D0p: olli 1732 F...m pulseaudio Date: Mon Nov 11 12:08:47 2013 HibernationDevice: RESUME=UUID=99eff1be-4759-4df7-99d6-a91a4cf999ce InstallationDate: Installed on 2013-10-19 (22 days ago) InstallationMedia: Ubuntu 13.10 "Saucy Salamander" - Release amd64 (20131016.1) MachineType: LENOVO 4174PEG MarkForUpload: True ProcFB: ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.11.0-13-generic root=UUID=e773c67a-283e-4a5d-b1ab-6000e6926d63 ro quiet splash pci=noacpi RelatedPackageVersions: linux-restricted-modules-3.11.0-13-generic N/A linux-backports-modules-3.11.0-13-generic N/A linux-firmware 1.116 SourcePackage: linux UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 04/11/2013 dmi.bios.vendor: LENOVO dmi.bios.version: 8CET57WW (1.37 ) dmi.board.asset.tag: Not Available dmi.board.name: 4174PEG dmi.board.vendor: LENOVO dmi.board.version: Not Available dmi.chassis.asset.tag: No Asset Information dmi.chassis.type: 10 dmi.chassis.vendor: LENOVO dmi.chassis.version: Not Available dmi.modalias: dmi:bvnLENOVO:bvr8CET57WW(1.37):bd04/11/2013:svnLENOVO:pn4174PEG:pvrThinkPadT420s:rvnLENOVO:rn4174PEG:rvrNotAvailable:cvnLENOVO:ct10:cvrNotAvailable: dmi.product.name: 4174PEG dmi.product.version: ThinkPad T420s dmi.sys.vendor: LENOVO ** Affects: linux (Ubuntu) Importance: Undecided Status: New ** Tags: amd64 apport-bug saucy -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1250027 Title: Lenovo ThinkPad T420s fails to boot with discrete graphics To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1250027/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs