Linux command line parameters are not copied to upgrade initramfs

[AloisMahdal]

Actual behavior

Linux command line parameters added before calling leapp upgrade don't affect upgrade process initramfs.

To Reproduce
Steps to reproduce the behavior

1. Add some parameters to Linux command line (GRUB_CMDLINE in /etc/default/grub)
2. install leapp
3. leapp upgrade --debug
4. reboot
5. observe Linux command line

Expected behavior

The parameters added above should be present in the upgrade command line.

System information (please complete the following information):

leapp-0.5.0-1.201904011532Z.d0a3c9a.master.el7_6.noarch
leapp-repository-0.5.0-1.201904011554Z.11ac42d.master.el7_6.noarch

[bocekm]

For creating a new grub entry for rebooting into our initramfs, we use grubby with the --copy-default option:
https://github.com/oamg/leapp-repository/blob/master/repos/system_upgrade/el7toel8/actors/addupgradebootentry/libraries/library.py#L18
This option takes whatever the current default boot entry has for kernel arguments and adds them for the new boot entry too.

I did a test:

1. I added a new kernel argument rd.debug=0 by:

   1. editing GRUB_CMDLINE_LINUX in /etc/default/grub
   2. and then by propagating this change to the boot partition using grub2-mkconfig -o /boot/grub2/grub.cfg. You can find that this is necessary to do in https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html/system_administrators_guide/sec-customizing_the_grub_2_configuration_file.

2. I ran leapp upgrade and the new boot entry for 'RHEL Upgrade Initramfs' has the rd.debug=0 among the kernel arguments.

   Click to see a snippet of the generated _/boot/grub2/grub.cfg_:

    menuentry 'RHEL Upgrade Initramfs' --class red --class gnu-linux --class gnu --class os --unrestricted $menuentry_id_option 'gnulinux-3.10.0-957.el7.x86_64-advanced-3199373c-4210-4068-a5c5-6346e2c3a246' {
            load_video
            set gfxpayload=keep
            insmod gzio
            insmod part_msdos
            insmod xfs
            set root='hd0,msdos1'
            if [ x$feature_platform_search_hint = xy ]; then
            search --no-floppy --fs-uuid --set=root --hint='hd0,msdos1'  3199373c-4210-4068-a5c5-6346e2c3a246
            else
            search --no-floppy --fs-uuid --set=root 3199373c-4210-4068-a5c5-6346e2c3a246
            fi
            linux16 /boot/vmlinuz-upgrade.x86_64 root=UUID=3199373c-4210-4068-a5c5-6346e2c3a246 ro console=tty0 console=ttyS0,115200 crashkernel=auto net.ifnames=0 rhgb quiet rd.debug=1 debug enforcing=0 rd.plymouth=0 plymouth.enable=0
            initrd16 /boot/initramfs-upgrade.x86_64.img
    }
    menuentry 'Red Hat Enterprise Linux Server (3.10.0-957.el7.x86_64) 7.6 (Maipo)' --class red --class gnu-linux --class gnu --class os --unrestricted $menuentry_id_option 'gnulinux-3.10.0-957.el7.x86_64-advanced-3199373c-4210-4068-a5c5-6346e2c3a246' {
            load_video
            set gfxpayload=keep
            insmod gzio
            insmod part_msdos
            insmod xfs
            set root='hd0,msdos1'
            if [ x$feature_platform_search_hint = xy ]; then
            search --no-floppy --fs-uuid --set=root --hint='hd0,msdos1'  3199373c-4210-4068-a5c5-6346e2c3a246
            else
            search --no-floppy --fs-uuid --set=root 3199373c-4210-4068-a5c5-6346e2c3a246
            fi
            linux16 /boot/vmlinuz-3.10.0-957.el7.x86_64 root=UUID=3199373c-4210-4068-a5c5-6346e2c3a246 ro console=tty0 console=ttyS0,115200 crashkernel=auto net.ifnames=0 rhgb quiet rd.debug=1
            initrd16 /boot/initramfs-3.10.0-957.el7.x86_64.img