RE: [PATCH] rootfs: run kernel-install after update-initramfs

["'Arjunan, Srinu' via isar-users" <isar-users@googlegroups.com>]

> Err, where/how do you define "primary" and "secondary" EFI bootloaders?
> Note that EBG is isar-cip-core, and there we definitely do not have such a concept. Can you
> elaborate what you want to achieve?

In our downstream project, we use a combination of EBG and systemd-boot, along with UKI (ukify) images.

EBG acts as the primary bootloader to enable watchdog support during early boot,
while systemd-boot is used as a secondary bootloader to select the appropriate Btrfs snapshot along with its corresponding UKI image.

If the system fails to be successfully “blessed” (e.g., due to issues detected during validation of a newly created Btrfs snapshot),
 we need a mechanism to fall back to a previously working snapshot and its associated UKI image. This fallback selection is handled by systemd-boot.

To support this flow, the WIC plugin expects /boot/EFI/Linux to contain the unified kernel image required for the first boot.

Therefore, we run kernel-install after update-initramfs to ensure that the unified kernel image is properly 
generated and placed in the expected location.

Many thanks,
Srinu

-----Original Message-----
From: Kiszka, Jan (FT RPD CED) <jan.kiszka@siemens.com> 
Sent: 15 April 2026 18:35
To: Arjunan, Srinu (FT FDS CES LX PBU 2) <srinuvasan.a@siemens.com>; isar-users@googlegroups.com
Cc: K L, Shivaschandra (FT FDS CES LX PBU 1) <shivaschandra.k-l@siemens.com>
Subject: Re: [PATCH] rootfs: run kernel-install after update-initramfs

On 15.04.26 14:55, srinuvasan.a via isar-users wrote:
> From: srinuvasan <srinuvasan.a@siemens.com>
> 
> When efibootguard is used as the primary bootloader and systemd-boot 
> as secondary, the WIC plugin expects /boot/EFI/Linux to contain a 
> unified kernel image for first boot.
> 

Err, where/how do you define "primary" and "secondary" EFI bootloaders?
Note that EBG is isar-cip-core, and there we definitely do not have such a concept. Can you elaborate what you want to achieve?

> Run kernel-install after update-initramfs to ensure the unified kernel 
> image is generated and placed correctly.
> 
> Invoke kernel-install for UKI generation only when:
> - ukify binary is available
> - /usr/lib/kernel/install.conf exists
> 
> Signed-off-by: Shivaschandra KL <shivaschandra.k-l@siemens.com>
> Signed-off-by: srinuvasan <srinuvasan.a@siemens.com>
> ---
>  meta/classes-recipe/rootfs.bbclass | 20 +++++++++++++++++---
>  1 file changed, 17 insertions(+), 3 deletions(-)
> 
> diff --git a/meta/classes-recipe/rootfs.bbclass 
> b/meta/classes-recipe/rootfs.bbclass
> index a9233111..9024f006 100644
> --- a/meta/classes-recipe/rootfs.bbclass
> +++ b/meta/classes-recipe/rootfs.bbclass
> @@ -14,10 +14,20 @@ ROOTFS_DISTRO ?= "${DISTRO}"
>  ROOTFS_USE_DRACUT ??= ""
>  
>  def initramfs_generator_cmdline(d):
> -    rootfs_packages =  d.getVar('ROOTFS_PACKAGES') or ''
> +    rootfs_packages = d.getVar('ROOTFS_PACKAGES') or ''
> +
>      if 'dracut' in rootfs_packages or bb.utils.to_boolean(d.getVar('ROOTFS_USE_DRACUT')):
> -        return "dracut --force --kver \"$kernel_version\""
> -    return "update-initramfs -u -v -k \"$kernel_version\""
> +        return 'dracut --force --kver "$kernel_version"'
> +
> +    cmdline = 'update-initramfs -u -v -k "$kernel_version"'
> +
> +    cmdline += (
> +        '; command -v ukify >/dev/null && [ -f /usr/lib/kernel/install.conf ] && '

Who is using ukify? No one in isar or isar-cip-core at least. Are you referring to an out-of-tree wic plugin with these changes?

In-tree (Isar), we still need to enable
meta/scripts/lib/wic/plugins/source/bootimg-efi-isar.py to generate UKIs. But that would be systemd-boot UKI-only, no EBG then.

Jan

> +        'kernel-install add "$kernel_version" "/boot/${kernel##*/}" '
> +        '"/boot/initrd.img-$kernel_version" || :'
> +    )
> +
> +    return cmdline
>  
>  ROOTFS_PACKAGES ?= ""
>  ROOTFS_VARDEPS ?= ""
> @@ -627,6 +637,10 @@ python do_generate_initramfs_setscene () {  }
>  
>  rootfs_generate_initramfs[progress] = "custom:rootfs_progress.InitrdProgressHandler"
> +rootfs_generate_initramfs:prepend() {
> +    export kernel
> +}
> +
>  rootfs_generate_initramfs() {
>      if [ -n "$(sudo find '${ROOTFSDIR}/boot' -type f -name 'vmlinu[xz]*')" ]; then
>          for kernel in ${ROOTFSDIR}/boot/vmlinu[xz]-*; do


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Linux Expert Center

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