flash-kernel can't be properly disabled

[Juerg Haefliger]

Per the man page:

/etc/flash-kernel/machine
  If present this can be used to override the machine autodetection. The contents must be a
  string which matches an entry in the database. Or `none' to disable flash-kernel.

However, if that file contains 'none, flash-kernel bombs out with a non-0 exit status:

$ cat /etc/flash-kernel/machine
none

$ sudo flash-kernel
Unsupported platform 'none'.
$ echo $?
1

If disabled, the exit status should be 0. Otherwise installation of packages that call flash-kernel in a postinst hook will fail.

[Juerg Haefliger (juergh)]

Processing triggers for linux-image-6.2.0-1016-raspi (6.2.0-1016.18) ...
/etc/kernel/postinst.d/initramfs-tools:
update-initramfs: Generating /boot/initrd.img-6.2.0-1016-raspi
flash-kernel: deferring update (trigger activated)
/etc/kernel/postinst.d/zz-flash-kernel:
flash-kernel: deferring update (trigger activated)
Processing triggers for flash-kernel (3.106ubuntu14) ...
Unsupported platform 'none'.
dpkg: error processing package flash-kernel (--configure):
 installed flash-kernel package post-installation script subprocess returned error exit status 1
Errors were encountered while processing:
 flash-kernel
E: Sub-process /usr/bin/dpkg returned an error code (1)

[Heinrich Schuchardt (xypron)]

Hello Juerg,

get_machine() and its caller would have to be changed in file 'functions'.

I wonder why you have to use 'none' in /etc/flash-kernel/machine. Could you, please, describe your usage scenario. In which situation do you have neither a valid value in /proc/device-tree/model nor in /etc/flash-kernel/machine? What would write 'none' to /etc/flash-kernel/machine?

Would it help to return $? = 0 if /proc/device-tree/model does not exist? This would allow to use the same image (with flash-kernel) both on a system with ACPI as well as on one with a device-tree.

Best regards

Heinrich

[Juerg Haefliger (juergh)]

I just want to disable flash-kernel manually as I'm testing/installing different kernels and don't want it to run after every package installation.

The man page says I can do that but the code won't let me, so it's broken. Looking at the code, it does the correct thing if env variable FK_MACHINE == none so should also exit 0 after echo none > /etc/flash-kernel/machine.

I've opened this but it probably doesn't go anywhere: https://salsa.debian.org/installer-team/flash-kernel/-/merge_requests/51

[Juerg Haefliger (juergh)]

This has been merged in upstream debian:

https://salsa.debian.org/installer-team/flash-kernel/-/commit/7b94224bede20da9df1feaf52efa6215bb19c919