Created upstream issue https://github.com/osbuild/osbuild-composer/issues/1819

Hi Tomas,

To keep consistent with the previous images with kdump enabled, I guess you need to specify crashkernel after removed 'crashkernel=auto'.

I am asking kairui for more suggestions.

Hi Kairui,

Do you have any comments in specifying it? Because I found it was not always added when new kernel installed.

eg."crashkernel=1G-4G:192M,4G-64G:256M,64G-:512M" on x86_64, how about other platforms?

Hi,

Starting from RHEL9, crashkernel will have a default value included in the kernel package, on a installed system there will be a file available as /lib/modules/$(uname -r)/crashkernel.default which contains the default crashkernel value for that specified kernel version. System installer should set crashkernel value based on this file.

You can check bz1974638 and bz1942398 for more info.

Hi Frank.

Please correct me if I'm wrong. After going through the bugs linked in comment #3, it seems to me that Image builder should simply append the content of "${rootfs}/lib/modules/${kernelver}/crashkernel.default" provided by the installed kernel package to the kernel command line options used by the image. Is that correct?

(In reply to Tomáš Hozza from comment #5)
> Hi Frank.
> 
> Please correct me if I'm wrong. After going through the bugs linked in
> comment #3, it seems to me that Image builder should simply append the
> content of "${rootfs}/lib/modules/${kernelver}/crashkernel.default" provided
> by the installed kernel package to the kernel command line options used by
> the image. Is that correct?
Yes, I think so.

Here are examples of my systems:
# cat /lib/modules/5.14.0-8.el9.x86_64/crashkernel.default 
crashkernel=1G-4G:192M,4G-64G:256M,64G-:512M
# cat /lib/modules/5.14.0-11.el9.aarch64/crashkernel.default 
crashkernel=2G-:448M

There have been multiple issued identified with this change, which will require changes to osbuild as well as image definitions in osbuild-composer. More information is in the upstream issue https://github.com/osbuild/osbuild-composer/issues/1819#issuecomment-966199997

There is a new change in RHEL9.0GA in bug https://bugzilla.redhat.com/show_bug.cgi?id=1895258, the /lib/modules/.../crashkernel.default has been dropped as well,  all have been moved to kexec-tools. There is a kdumpctl option to get the correct default values.

Coiby, can you add more details here about how to get the proper value for os-builder?

Hi Tomáš,

kexec-tools now would set up kernel crashkernel for osbuild in kernel hook [1] as resolved in Bug 2024976. So now osbuild can simply drop crashkernel=auto and there is no need for osbuild to retrieve the default crashkernel value itself.
    
[1] https://src.fedoraproject.org/rpms/kexec-tools/c/ddd428a1d0d72bee2a8459b1a81541bcd0676873?branch=rawhide

In the interest of time I went ahead and submitted a change in upstream - https://github.com/osbuild/osbuild-composer/pull/2262

Once Bug #2024976 is resolved, the appropriate crashkernel value will be set when RHEL-9.0 image is built.

Note for QE:

The step to verify this change are:
- Before Bug #2024976 is resolved, check that RHEL EC2 and guest image do not have 'crashkernel=auto' on the kernel command line. In fact there won't be any 'crashkernel' option set.
- After Bug #2024976 is resolved, check that RHEL EC2 and guest image do not have 'crashkernel=auto' on the kernel command line. The 'crashkernel' option will be set to the appropriate value by kexec-tools package.

This is covered by image-tests.sh so fairly easy to verify for QE.

Uploaded the latest RHEL-9.0-20220227.3(rhel-ec2-9.0-20220227.3.x86_64.raw) to ec2 and crashkernel is set correctly.
# cat /proc/cmdline 
BOOT_IMAGE=(hd0,gpt3)/vmlinuz-5.14.0-69.el9.x86_64 root=UUID=da88f4cb-fcdd-4f87-9eb7-40155e2c75bc console=ttyS0,115200n8 console=tty0 net.ifnames=0 rd.blacklist=nouveau nvme_core.io_timeout=4294967295 crashkernel=1G-4G:192M,4G-64G:256M,64G-:512M

Fixed by osbuild-composer 44.

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory (new packages: osbuild-composer), and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2022:2522