Would it be possible for you to test the latest upstream kernel? Refer to https://wiki.ubuntu.com/KernelMainlineBuilds . Please test the latest v4.9 kernel[0].
If this bug is fixed in the mainline kernel, please add the following tag 'kernel-fixed-upstream'. If the mainline kernel does not fix this bug, please add the tag: 'kernel-bug-exists-upstream'. Once testing of the upstream kernel is complete, please mark this bug as "Confirmed". Thanks in advance. [0] http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.9-rc2 ** Changed in: linux (Ubuntu) Importance: Undecided => High ** 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/1635891 Title: Random hangs after upgrade to 4.4.0-45, possibly cgroup related Status in linux package in Ubuntu: Incomplete Bug description: Apologize in advance is anything is missing from this bug report. After upgrading to 4.4.0-45 we have started to experience random kernel lockups. I have attached a sample from the syslog which I managed to catch after one of these events. In other cases, nothing was written to the syslog. I notice that the cgroup system features here and there in the log, and the hanging server uses cgroups and namespaces heavily, so I suspect it is related. Sadly I don't know enough of the kernel to decipher the error I got further than that. Another unusual thing we do on this server, which may possibly be related, is that we regularly clear the caches ("echo 3 > /proc/sys/vm/drop_caches") /Pehr ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: linux-image-4.4.0-45-generic 4.4.0-45.66 ProcVersionSignature: Ubuntu 4.4.0-45.66-generic 4.4.21 Uname: Linux 4.4.0-45-generic x86_64 AlsaDevices: total 0 crw-rw---- 1 root audio 116, 1 Oct 22 22:52 seq crw-rw---- 1 root audio 116, 33 Oct 22 22:52 timer AplayDevices: Error: [Errno 2] No such file or directory: 'aplay' ApportVersion: 2.20.1-0ubuntu2.1 Architecture: amd64 ArecordDevices: Error: [Errno 2] No such file or directory: 'arecord' AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/seq', '/dev/snd/timer'] failed with exit code 1: Date: Sat Oct 22 23:37:59 2016 HibernationDevice: RESUME=/dev/mapper/template--16--vg-swap_1 InstallationDate: Installed on 2016-04-22 (183 days ago) InstallationMedia: Ubuntu-Server 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.3) IwConfig: Error: [Errno 2] No such file or directory: 'iwconfig' Lsusb: Error: command ['lsusb'] failed with exit code 1: MachineType: VMware, Inc. VMware Virtual Platform PciMultimedia: ProcFB: 0 svgadrmfb ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-4.4.0-45-generic root=/dev/mapper/template--16--vg-root ro cgroup_enable=memory swapaccount=1 RelatedPackageVersions: linux-restricted-modules-4.4.0-45-generic N/A linux-backports-modules-4.4.0-45-generic N/A linux-firmware 1.157.4 RfKill: Error: [Errno 2] No such file or directory: 'rfkill' SourcePackage: linux UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 09/17/2015 dmi.bios.vendor: Phoenix Technologies LTD dmi.bios.version: 6.00 dmi.board.name: 440BX Desktop Reference Platform dmi.board.vendor: Intel Corporation dmi.board.version: None dmi.chassis.asset.tag: No Asset Tag dmi.chassis.type: 1 dmi.chassis.vendor: No Enclosure dmi.chassis.version: N/A dmi.modalias: dmi:bvnPhoenixTechnologiesLTD:bvr6.00:bd09/17/2015:svnVMware,Inc.:pnVMwareVirtualPlatform:pvrNone:rvnIntelCorporation:rn440BXDesktopReferencePlatform:rvrNone:cvnNoEnclosure:ct1:cvrN/A: dmi.product.name: VMware Virtual Platform dmi.product.version: None dmi.sys.vendor: VMware, Inc. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1635891/+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