Proposal

General Information

openEuler-21.09-x86_64.qcow2.xz KVM image has /etc/grub2-efi.cfg that is symbolic link to /boot/grub2/efi/EFI/openEuler/grub.cfg, users might need to use grubby to change kernel boot parameters like below

grubby --grub2 --args="apparmor=0" --remove-args="rhgb quiet" --update-kernel /boot/vmlinuz-5.10.0-5.10.0.24.oe1.x86_64

to run light weight k3s kubernetes cluster due to k3s issue https://github.com/rancher/k3os/issues/702, but above grubby command only changed /etc/grub2-efi.cfg, ignored /etc/grub2.cfg which is symbolic link to /boot/grub2/grub.cfg that the VM will actually use unless users specifically configured VM to use EFI to boot the VM https://fedoraproject.org/wiki/Using_UEFI_with_QEMU, which I think most of users don't do that.

https://docs.fedoraproject.org/en-US/fedora/rawhide/system-administrators-guide/kernel-module-driver-configuration/Working_with_the_GRUB_2_Boot_Loader/#sec-Making_Persistent_Changes_to_a_GRUB_2_Menu_Using_the_grubby_Tool

I recommend to either remove /etc/grub2-efi.cfg or maybe documents it somewhere about how to change the VM kernel boot parameter according to if EFI configured or not in VM qemu.

How to reproduce the issue

1. Download https://repo.openeuler.org/openEuler-21.09/virtual_machine_img/x86_64/openEuler-21.09-x86_64.qcow2.xz and ran the openEuler image in KVM,

2. grubby --grub2 --args="apparmor=0" --remove-args="rhgb quiet" --update-kernel /boot/vmlinuz-5.10.0-5.10.0.24.oe1.x86_64

3. reboot

4. cat /proc/cmdline to check if kernel has "apparmor=0" set