This is not limited to ppc64el and at least applies to s390x, too.
** Also affects: ubuntu-power-systems
Importance: Undecided
Status: New
** Changed in: ubuntu-power-systems
Status: New => Triaged
** Changed in: ubuntu-power-systems
Importance: Undecided => Medium
** Changed in: ubuntu-power-systems
Assignee: (unassigned) => Canonical Kernel Team (canonical-kernel-team)
--
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/1793369
Title:
Ubuntu18.10:Witherspoon:DD2.2 - Sysrq trigger disabled when writing to
/proc/sysrq-trigger
Status in The Ubuntu-power-systems project:
Triaged
Status in linux package in Ubuntu:
Triaged
Status in linux source package in Cosmic:
Triaged
Bug description:
== Comment: #0 - Praveen K. Pandey <praveen.pan...@in.ibm.com> - 2018-09-19
04:49:39 ==
---Problem Description---
[Witherspoon-DD2.2][Ubu 18.10] [4.18.0-7-generic ] : Sysrq trigger disabled
when writing to /proc/sysrq-trigger
while testing kdump trying trigger kdump panic via /proc/sysrq-trigger it
failed as : SysRq : This sysrq operation is disabled
LOG:
root@test:~# cat /proc/sys/kernel/sysrq
176
root@test:~# echo c > /proc/sysrq-trigger
root@test:~# dmesg
[ 380.340051] mlx5_core 0000:01:00.1 enp1s0f1: Self test out: status
flags(0x2)
[ 389.404239] sysrq: SysRq : This sysrq operation is disabled.
root@test~# cat /boot/config-4.18.0-7-generic | grep CONFIG_MAGIC_SYSRQ
CONFIG_MAGIC_SYSRQ=y
CONFIG_MAGIC_SYSRQ_DEFAULT_ENABLE=0x01b6
CONFIG_MAGIC_SYSRQ_SERIAL=y
root@test:~# cat /etc/sysctl.conf | grep kernel.sysrq
#kernel.sysrq=438
root@test:~# kdump-config show
DUMP_MODE: kdump
USE_KDUMP: 1
KDUMP_SYSCTL: kernel.panic_on_oops=1
KDUMP_COREDIR: /var/crash
crashkernel addr:
/var/lib/kdump/vmlinuz: symbolic link to /boot/vmlinux-4.18.0-7-generic
kdump initrd:
/var/lib/kdump/initrd.img: symbolic link to
/var/lib/kdump/initrd.img-4.18.0-7-generic
current state: ready to kdump
kexec command:
/sbin/kexec -p
--command-line="root=UUID=c0302064-c5a3-49a7-8bd4-402283e6fcbe ro quiet splash
nr_cpus=1 systemd.unit=kdump-tools.service irqpoll noirqdistrib nousb"
--initrd=/var/lib/kdump/initrd.img /var/lib/kdump/vmlinuz
root@test:~#
Regards
Praveen
== Comment: #2 - Praveen K. Pandey <praveen.pan...@in.ibm.com> - 2018-09-19
05:16:11 ==
when i enable in /etc/sysctl.conf it works . i append below value in
sysctl.conf
echo "kernel.sysrq = 1" >> /etc/sysctl.conf
I think this is should be enable by default in ubuntu 18.10 as
earlier ubuntu distro it has , not sure why it got removed as kdump
mechanism require this .
Praveen
Regards
To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu-power-systems/+bug/1793369/+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
