We believe this problem is understood, and Microsoft have a developer working on upstream fixes for this. Initial patches were submitted here: https://lkml.org/lkml/2014/12/2/662, though I believe they are being revised currently.
-- 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/1292400 Title: task systemd-udevd:1906 blocked for more than 120 seconds. Status in linux package in Ubuntu: Confirmed Bug description: System log shows repeated incidents of "task systemd-udevd:1906 blocked for more than 120 seconds." ProblemType: Bug DistroRelease: Ubuntu 14.04 Package: linux-image-3.13.0-17-generic 3.13.0-17.37 [modified: boot/vmlinuz-3.13.0-17-generic] ProcVersionSignature: Ubuntu 3.13.0-17.37-generic 3.13.6 Uname: Linux 3.13.0-17-generic x86_64 ApportVersion: 2.13.3-0ubuntu1 Architecture: amd64 AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/seq', '/dev/snd/timer'] failed with exit code 1: CurrentDesktop: XFCE Date: Fri Mar 14 08:54:36 2014 HibernationDevice: RESUME=UUID=0d223c65-8c7e-41b4-95b3-05b22ff4679b InstallationDate: Installed on 2014-03-12 (1 days ago) InstallationMedia: Xubuntu 14.04 LTS "Trusty Tahr" - Alpha amd64 (20140312) IwConfig: eth0 no wireless extensions. lo no wireless extensions. Lspci: Lsusb: Error: command ['lsusb'] failed with exit code 1: unable to initialize libusb: -99 MachineType: Microsoft Corporation Virtual Machine ProcFB: 0 EFI VGA ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.13.0-17-generic.efi.signed root=UUID=61b52c1b-300d-4c30-8966-db1745f4a4bc ro video:hyperv_fb=1920x1080 quiet splash vt.handoff=7 RelatedPackageVersions: linux-restricted-modules-3.13.0-17-generic N/A linux-backports-modules-3.13.0-17-generic N/A linux-firmware 1.126 RfKill: SourcePackage: linux UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 11/26/2012 dmi.bios.vendor: Microsoft Corporation dmi.bios.version: Hyper-V UEFI Release v1.0 dmi.board.asset.tag: None dmi.board.name: Virtual Machine dmi.board.vendor: Microsoft Corporation dmi.board.version: Hyper-V UEFI Release v1.0 dmi.chassis.asset.tag: 6485-6574-9248-6162-4701-6267-50 dmi.chassis.type: 3 dmi.chassis.vendor: Microsoft Corporation dmi.chassis.version: Hyper-V UEFI Release v1.0 dmi.modalias: dmi:bvnMicrosoftCorporation:bvrHyper-VUEFIReleasev1.0:bd11/26/2012:svnMicrosoftCorporation:pnVirtualMachine:pvrHyper-VUEFIReleasev1.0:rvnMicrosoftCorporation:rnVirtualMachine:rvrHyper-VUEFIReleasev1.0:cvnMicrosoftCorporation:ct3:cvrHyper-VUEFIReleasev1.0: dmi.product.name: Virtual Machine dmi.product.version: Hyper-V UEFI Release v1.0 dmi.sys.vendor: Microsoft Corporation --- ApportVersion: 2.13.3-0ubuntu1 Architecture: amd64 AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/seq', '/dev/snd/timer'] failed with exit code 1: CurrentDesktop: XFCE DistroRelease: Ubuntu 14.04 HibernationDevice: RESUME=UUID=0d223c65-8c7e-41b4-95b3-05b22ff4679b InstallationDate: Installed on 2014-03-12 (1 days ago) InstallationMedia: Xubuntu 14.04 LTS "Trusty Tahr" - Alpha amd64 (20140312) IwConfig: eth0 no wireless extensions. lo no wireless extensions. Lspci: Lsusb: Error: command ['lsusb'] failed with exit code 1: unable to initialize libusb: -99 MachineType: Microsoft Corporation Virtual Machine Package: linux (not installed) ProcFB: 0 EFI VGA ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.13.0-17-generic.efi.signed root=UUID=61b52c1b-300d-4c30-8966-db1745f4a4bc ro video:hyperv_fb=1920x1080 quiet splash vt.handoff=7 ProcVersionSignature: Ubuntu 3.13.0-17.37-generic 3.13.6 RelatedPackageVersions: linux-restricted-modules-3.13.0-17-generic N/A linux-backports-modules-3.13.0-17-generic N/A linux-firmware 1.126 RfKill: Tags: trusty Uname: Linux 3.13.0-17-generic x86_64 UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo _MarkForUpload: True dmi.bios.date: 11/26/2012 dmi.bios.vendor: Microsoft Corporation dmi.bios.version: Hyper-V UEFI Release v1.0 dmi.board.asset.tag: None dmi.board.name: Virtual Machine dmi.board.vendor: Microsoft Corporation dmi.board.version: Hyper-V UEFI Release v1.0 dmi.chassis.asset.tag: 6485-6574-9248-6162-4701-6267-50 dmi.chassis.type: 3 dmi.chassis.vendor: Microsoft Corporation dmi.chassis.version: Hyper-V UEFI Release v1.0 dmi.modalias: dmi:bvnMicrosoftCorporation:bvrHyper-VUEFIReleasev1.0:bd11/26/2012:svnMicrosoftCorporation:pnVirtualMachine:pvrHyper-VUEFIReleasev1.0:rvnMicrosoftCorporation:rnVirtualMachine:rvrHyper-VUEFIReleasev1.0:cvnMicrosoftCorporation:ct3:cvrHyper-VUEFIReleasev1.0: dmi.product.name: Virtual Machine dmi.product.version: Hyper-V UEFI Release v1.0 dmi.sys.vendor: Microsoft Corporation To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1292400/+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