Foregoing both grub and systemd-boot

I really like the idea the nmbl project is exploring.

Basically grub gets replaced with a uki. And if the kernel in the uki is the same as the one the os being booted uses, a lot of code is removed from the bootstrap process.

Even if the kernel the os being booted uses is a different kernel there are a lot of benefits. No more grub. No systemd-boot. Just linux.

If you are lucky enough to be able to use coreboot you could be running nothing but linux.

Who else has been exposed to the nmbl-poc project here? What did you think?

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A uki is kernel + initrd + command line that are all signed (my understanding is limited).

Not sure what you comment about uki kernel not being the os kernel is getting at. The uki kernel is the os kernel surely?

Isn’t what nmbl is doing the same as sdboot of a uki?
But as nmbl is usimg shim its not as secure as proposed sdboot + uki?

Again my understanding is limited in this area.

See the information published by fizuxchyk by following the provided hyperlinks as I am positive I could not do justice to the topic on my own.

systemd-boot is currently not signed and would not be a good candidate to sign directly by MS so would likely also use shim if it ever gets included in fedora as a signed efi binary.

The uki of nmbl could kexec to a different linux kernel for the OSs use. Or it could switchroot if the kernel stays the same.

The uki of nmbl could be used in place of grub to boot other OSs though without chainloading. That is also explained. One use case would have nmbl set next boot efivars to obtain similar effect. Lots of flexibility in what could be included in the nmbl uki like menu, graphics, network boot, or whatever.

The nmbl uki would have all the hardware support of linux and all the developer community of linux which is not the case for other boot loaders.

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I assumed that because both links are named nmbl they referred to the same url, I had followed the 2nd nmbl link. Marta’s explanation is very helpful.

There is a write of nmbl on https://lwn.net/ (paywalled this week, free next week)

See “ Giving bootloaders the boot with nmbl” and the analysis in the comments is very interesting.

Funny, Fedora Atomic Distros could just skip systemd-boot. But with all the bootc images I am not sure how the update and boot process is done anymore.

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