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No more boot loader: Please use the kernel instead

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Re: No more boot loader: Please use the kernel instead

#2
I personally think they're moving in the wrong direction. I'd rather have "NMIRFS" (no more initramfs). Eg, a smarter bootloader that understands all bootable filesystems and cooperates with the kernel to pre-load modules needed for boot and obviates the need for initramfs.

FreeBSD's loader does this, and its so much easier to deal with. Eg, it understands ZFS, and can pre-load storage driver modules and zfs.ko for the kernel, so that the kernel has everything it needs to boot up. It also understands module dependencies, and will preload all modules that are needed for a module you specify (similar to modprobe).

Re: No more boot loader: Please use the kernel instead

#5
I can't open the .odp file right now, but:

>We (Red Hat boot loader engineering) will present our solution to this problem, which is to use the Linux kernel as its own bootloader. Loaded by the EFI stub on UEFI, and packed into a unified kernel image (UKI), the kernel, initramfs, and kernel command line, contain everything they need to reach the final boot target. All necessary drivers, filesystem support, and networking are already built in and code duplication is avoided.

That has been doable for a few years already. What's the new part?

Re: No more boot loader: Please use the kernel instead

#7
post #2

I personally think they're moving in the wrong direction. I'd rather have "NMIRFS" (no more initramfs). Eg, a smarter bootloader that understands all bootable filesystems and cooperates with the kernel to pre-load modules needed for boot and obviates the need for initramfs. FreeBSD's loader does this, and its so much easier to deal with. Eg, it understands ZFS, and can pre-load storage driver modules and zfs.ko for t…

The Linux kernel does not require an initramfs. You can build a kernel with everything compiled in; with no modules needed at all. Initramfs is used for generic kernels where you don't know beforehand which features will be required. This allows you to avoid wasting RAM on features you don't use. But it is optional.

Re: No more boot loader: Please use the kernel instead

#8

Isn't one of the use cases in GRUB choosing which kernel you want to load?

That’s the neat part - you install GRUB if that’s something you care about. For the 98+% who will always use the newest kernel, and can tell the system to (hypothetically) use a different kernel on future reboots after the system has loaded, it won’t be an issue.

Re: No more boot loader: Please use the kernel instead

#9
post #2

I personally think they're moving in the wrong direction. I'd rather have "NMIRFS" (no more initramfs). Eg, a smarter bootloader that understands all bootable filesystems and cooperates with the kernel to pre-load modules needed for boot and obviates the need for initramfs. FreeBSD's loader does this, and its so much easier to deal with. Eg, it understands ZFS, and can pre-load storage driver modules and zfs.ko for t…

> I'd rather have "NMIRFS" (no more initramfs).

In many cases, you don't need initramfs. I rarely use one in embedded systems.

Re: No more boot loader: Please use the kernel instead

#10
post #2

I personally think they're moving in the wrong direction. I'd rather have "NMIRFS" (no more initramfs). Eg, a smarter bootloader that understands all bootable filesystems and cooperates with the kernel to pre-load modules needed for boot and obviates the need for initramfs. FreeBSD's loader does this, and its so much easier to deal with. Eg, it understands ZFS, and can pre-load storage driver modules and zfs.ko for t…

Linux has multiple choices for filesystems for root, even if you only count the most popular ones. And on top of that they could be encrypted by LUKS. Duplicating all that into the bootloader is what GRUB does, and poorly. Putting the kernel into the ESP is much better in that regard.
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