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0 pointsyjftsjthsd-h11mo ago0 comments

> I wanted to do a full NTFS solution but I couldn't find a bootloader I liked that would support booting from a NTFS partition.

Could you stick the Linux kernel and initramfs on the EFI boot partition as a UKI, and then just tell it about its rootfs being on the NTFS C drive? You don't really need any bootloader except the firmware's UEFI implementation on most modern PCs, and Linux supports NTFS.

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csdvrx11mo ago

> Could you stick the Linux kernel and initramfs on the EFI boot partition as a UKI

I considered that, even if it would go against the idea of having everything inside the Windows partition. I'd rather have had a shim in the EFI, with the UKI in C:\

The difficulty was bitlocker: my approach was a UKI with a small kernel and a few binaries to open the bitlocker volume and kexec the bigger kernel.

I was also exploring how to mark part of the NTFS volume as unusable to stick a different payload there.

The "ISO on a thumbdrive" was done to get baremetal boot working and out of the way, to see if I needed deeper changes to what had started as a 2 stages boot process, or if it was good enough as-as.

> Linux supports NTFS.

The kernel module is great!

I wish there was a linux distribution that could be run from either WSL or baremetal, to get more people familiar with baremetal linux.

yjftsjthsd-hOP11mo ago

> The difficulty was bitlocker: my approach was a UKI with a small kernel and a few binaries to open the bitlocker volume and kexec the bigger kernel.

Why not do that from the initramfs with the real kernel? I'm pretty sure that's how it works on a normal encrypted root Linux install

csdvrx11mo ago

I wanted to limit the space needed on the EFI, and keep as much as possible on the Windows partition because there's also the question of where the bitlocker key would go.

With something like a chainloader using a special part of the NTFS partition posing as bad blocks, Windows could "remove" this access easily, without having to touch the EFI partition or the boot variables.

j / k navigate · click thread line to collapse

0 comments

csdvrx11mo ago

> Could you stick the Linux kernel and initramfs on the EFI boot partition as a UKI

I considered that, even if it would go against the idea of having everything inside the Windows partition. I'd rather have had a shim in the EFI, with the UKI in C:\

The difficulty was bitlocker: my approach was a UKI with a small kernel and a few binaries to open the bitlocker volume and kexec the bigger kernel.

I was also exploring how to mark part of the NTFS volume as unusable to stick a different payload there.

The "ISO on a thumbdrive" was done to get baremetal boot working and out of the way, to see if I needed deeper changes to what had started as a 2 stages boot process, or if it was good enough as-as.

> Linux supports NTFS.

The kernel module is great!

I wish there was a linux distribution that could be run from either WSL or baremetal, to get more people familiar with baremetal linux.

yjftsjthsd-hOP11mo ago

> The difficulty was bitlocker: my approach was a UKI with a small kernel and a few binaries to open the bitlocker volume and kexec the bigger kernel.

Why not do that from the initramfs with the real kernel? I'm pretty sure that's how it works on a normal encrypted root Linux install

csdvrx11mo ago

I wanted to limit the space needed on the EFI, and keep as much as possible on the Windows partition because there's also the question of where the bitlocker key would go.

j / k navigate · click thread line to collapse