[Bug 1741860] [NEW] Use the kernel default for crashkernel offset

[Launchpad Bug Tracker]

You have been subscribed to a public bug by Ubuntu Foundations Team Bug Bot (crichton):

[Impact]

 * The value chosen for ppc64el of 128MB aligns with that of the kernel
default. That may change some day, so it would be best to let the kernel
decide what value it should use. If the value does change and the kernel
is not allowed to choose a value, this may stop the kernel from booting
on a production system.

[Test Case]

 Run `cat /etc/default/grub.d/kdump-tools.cfg`

 * Expected result: there is no offset specified at the end of the line
(.e.g, @128M).

 * Actual result: For Xenial, Bionic, Disco, and Eoan there are offsets
specified.

[Regression Potential]

 * Right now, the offset described in the kdump-tools.cfg aligns with
that of what the kernel would select, so since they are the same we
would expect no change in operation.


Original bug description follows:
-----------------------------------------

== Comment: #0 - Hari Krishna Bathini <hbathini at in.ibm.com> - 2018-01-08 01:06:41 ==
---Problem Description---
A default offset of 128MB is enforced for crashkernel by kdump-tools utility
overriding the kernel default.

While the kernel default offset for crashkernel is also 128MB, that may change
and the right thing to do would be to let the kernel decide on the offset of
crashkernel in the default scenario..

Get rid of "@128M" in kdump-tools.cfg file

Contact Information = hbathini at in.ibm.com

---uname output---
na

Machine Type = na

---Debugger---
A debugger is not configured

---Steps to Reproduce---
 # cat /etc/default/grub.d/kdump-tools.cfg
GRUB_CMDLINE_LINUX_DEFAULT="$GRUB_CMDLINE_LINUX_DEFAULT crashkernel=2G-4G:320M,4G-32G:512M,32G-64G:1024M,64G-128G:2048M,128G-:4096M at 128M"
---

The offset is specified via kdump-tools where as the kernel may be the right place to
set an offset by default..

Userspace tool common name: kdump-tools

The userspace tool has the following bit modes: 64-bit

Userspace rpm: kdump-tools

Userspace tool obtained from project website:  na

*Additional Instructions for hbathini at in.ibm.com:
-Attach ltrace and strace of userspace application.

== Comment: #3 - MAMATHA INAMDAR <mainamdar at in.ibm.com> - 2018-01-08 03:05:05 ==
This bug is opened to follow-up other bug based on the comment 19
https://bugzilla.linux.ibm.com/show_bug.cgi?id=152905#c19 (Canonical Launchpad 	1676884 )

** Affects: ubuntu-power-systems
     Importance: High
     Assignee: Canonical Kernel Team (canonical-kernel-team)
         Status: In Progress

** Affects: makedumpfile (Ubuntu)
     Importance: High
     Assignee: Connor Kuehl (connork)
         Status: In Progress

** Affects: makedumpfile (Ubuntu Xenial)
     Importance: High
     Assignee: Connor Kuehl (connork)
         Status: In Progress

** Affects: makedumpfile (Ubuntu Bionic)
     Importance: High
     Assignee: Connor Kuehl (connork)
         Status: In Progress

** Affects: makedumpfile (Ubuntu Disco)
     Importance: High
     Assignee: Connor Kuehl (connork)
         Status: In Progress

** Affects: makedumpfile (Ubuntu Eoan)
     Importance: High
     Assignee: Connor Kuehl (connork)
         Status: In Progress


** Tags: architecture-ppc64le bugnameltc-163190 patch ppc64el-kdump severity-critical targetmilestone-inin1804 triage-g
-- 
Use the kernel default for crashkernel offset
https://bugs.launchpad.net/bugs/1741860
You received this bug notification because you are a member of Ubuntu Sponsors Team, which is subscribed to the bug report.