bcache null pointer exception , recursive fault

[Ryan Harper]

1) # cat /proc/version_signature
Ubuntu 3.13.0-166.216-generic 3.13.11-ckt39

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: linux-image-generic 3.13.0.167.178
ProcVersionSignature: Ubuntu 3.13.0-166.216-generic 3.13.11-ckt39
Uname: Linux 3.13.0-166-generic x86_64
AlsaDevices:
 total 0
 crw-rw---- 1 root audio 116, 1 Mar 18 20:14 seq
 crw-rw---- 1 root audio 116, 33 Mar 18 20:14 timer
AplayDevices: Error: [Errno 2] No such file or directory: 'aplay'
ApportVersion: 2.14.1-0ubuntu3.29
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: Mon Mar 18 20:23:48 2019
IwConfig: Error: [Errno 2] No such file or directory: 'iwconfig'
Lsusb: Error: command ['lsusb'] failed with exit code 1: unable to initialize libusb: -99
MachineType: QEMU Standard PC (i440FX + PIIX, 1996)
PciMultimedia:

ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
ProcFB:

ProcKernelCmdLine: root=/dev/disk/by-id/virtio-boot-disk ds=nocloud-net;seedfrom=http://10.245.168.20:40373/ console=ttyS0 overlayroot=tmpfs ro systemd.mask=snapd.seeded.service systemd.mask=snapd.service iscsi_auto ip=:::::BOOTIF:dhcp BOOTIF=01-52-54-00-12-34-01
RelatedPackageVersions:
 linux-restricted-modules-3.13.0-166-generic N/A
 linux-backports-modules-3.13.0-166-generic N/A
 linux-firmware 1.127.24
RfKill: Error: [Errno 2] No such file or directory: 'rfkill'
SourcePackage: linux
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 04/01/2014
dmi.bios.vendor: SeaBIOS
dmi.bios.version: 1.12.0-1
dmi.chassis.type: 1
dmi.chassis.vendor: QEMU
dmi.chassis.version: pc-i440fx-disco
dmi.modalias: dmi:bvnSeaBIOS:bvr1.12.0-1:bd04/01/2014:svnQEMU:pnStandardPC(i440FX+PIIX,1996):pvrpc-i440fx-disco:cvnQEMU:ct1:cvrpc-i440fx-disco:
dmi.product.name: Standard PC (i440FX + PIIX, 1996)
dmi.product.version: pc-i440fx-disco
dmi.sys.vendor: QEMU

[Ryan Harper (raharper)]

Kernel oops when attempting to stop an online bcache device.

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This change was made by a bot.

[Sultan Alsawaf (kerneltoast)]

Hi, please test the following kernel to see if the issue is fixed: https://private-fileshare.canonical.com/~sultan/trusty-bcache-test1.tar.gz

It's a tarball containing kernel .deb files.