The kernel failed to mount the initial root filesystem, which should have been put into RAM by the bootloader. It's strange that this is failing, and even stranger that the failure is intermittent. It would be really nice to get the full dmesg from the kernel, but that's difficult when the kernel panics that early in boot.
Now that we know the problem is intermittent, I think the next reasonable step is to establish if this really is a regression since 4.4.0-28. How often does this happen in 4.4.0-31? If it's reasonably frequent and you can do enough successful reboots into 4.4.0-28 to give confidence that the bug doesn't exist there, then we could bisect to try and figure out which change introduced the bug. -- 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/1605731 Title: Kernel 4.4.0-31 Causes kernel panic at startup Status in linux package in Ubuntu: In Progress Status in linux source package in Xenial: In Progress Bug description: Latest kernel update 4.4.0-31 causes kernel panic at startup. Had to reboot with 4.4.0-28 which works fine. I have no idea if it's on all filesystems but I'm using btrfs. --- ApportVersion: 2.20.1-0ubuntu2.1 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC0: robi 3230 F.... pulseaudio /dev/snd/pcmC1D0p: robi 3230 F...m pulseaudio /dev/snd/controlC1: robi 3230 F.... pulseaudio CurrentDesktop: Unity DistroRelease: Ubuntu 16.04 HibernationDevice: RESUME=UUID=d64a307b-b7ea-4308-b997-0587321ff7ea InstallationDate: Installed on 2016-07-01 (21 days ago) InstallationMedia: Ubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1) MachineType: ASUSTeK COMPUTER INC. X750LN NonfreeKernelModules: nvidia_uvm nvidia_modeset wl nvidia Package: linux (not installed) ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/@/boot/vmlinuz-4.4.0-28-generic root=UUID=e075f560-d606-43a0-9cc3-5596a9416d30 ro rootflags=subvol=@ quiet splash ProcVersionSignature: Ubuntu 4.4.0-28.47-generic 4.4.13 RelatedPackageVersions: linux-restricted-modules-4.4.0-28-generic N/A linux-backports-modules-4.4.0-28-generic N/A linux-firmware 1.157.2 Tags: xenial Uname: Linux 4.4.0-28-generic x86_64 UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo _MarkForUpload: True dmi.bios.date: 02/19/2014 dmi.bios.vendor: American Megatrends Inc. dmi.bios.version: 201 dmi.board.asset.tag: To be filled by O.E.M. dmi.board.name: X750LN dmi.board.vendor: ASUSTeK COMPUTER INC. dmi.board.version: 1.0 dmi.chassis.asset.tag: To Be Filled By O.E.M. dmi.chassis.type: 3 dmi.chassis.vendor: To Be Filled By O.E.M. dmi.chassis.version: To Be Filled By O.E.M. dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr201:bd02/19/2014:svnASUSTeKCOMPUTERINC.:pnX750LN:pvr1.0:rvnASUSTeKCOMPUTERINC.:rnX750LN:rvr1.0:cvnToBeFilledByO.E.M.:ct3:cvrToBeFilledByO.E.M.: dmi.product.name: X750LN dmi.product.version: 1.0 dmi.sys.vendor: ASUSTeK COMPUTER INC. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1605731/+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
