I am trying to make a bootable kali linux usb and have it working for legacy bios computers. However, uefi is causing some trouble. The usb is split up into 3 partitions. The first is the efi/boot partition which is fat32. The second is the main partition with the regular filesystem (which i can see using a tool called diskgenius on my main computer which is running windows). The third is the linux swap partition. Currently it is booting into the grub menu but will not boot into linux. When I go to the grub command line I can use the 'ls' command to see the partitions, and if I use "ls (hd0, 1)" it will show me the efi/boot folders but if I try "ls (hd0,2)" or any other partition it says "unknown file system".
I had to add some bootx64.efi and grub.cfg files to get my usb to boot with uefi. I've added some modules to grub too and when I type the command "lsmod" I see the modules "ext2" and "part_gpt" so I assume that would include ext4 support, I am not sure why it's not working. Also have secure boot disabled. Any help would be greatly appreciated!
Here are the commands I've tried:
set prefix=(hd0,2)/boot/grub set root=(hd0,2) linuxefi /boot/vmlinuz-4.18.0-kali2-amd64 noconfig=sudo username=root hostname=kali initrdefi /boot/initrd.img-4.18.0-kali2-amd64
It gives the error "unkown filesystem" after the linuxefi command