how is booting possible using kernel image in disk?..

"Chan Kim" <ckim@xxxxxxxxxx> · Thu, 21 Oct 2021 21:53:31 +0900

Hello,
In my ubuntu 20.04 machine, 

ckim@ckim-ubuntu:~$ dmesg | grep 'Command'
[    0.000000] Command line: BOOT_IMAGE=/boot/vmlinuz-5.11.0-36-generic root=UUID=5252b177-1243-4d3f-8a1a-ec7d0dcae011 ro quiet splash vt.handoff=7
ckim@ckim-ubuntu:~$ mount | grep boot
/dev/sda2 on /boot/efi type vfat (rw,relatime,fmask=0077,dmask=0077,codepage=437,iocharset=iso8859-1,shortname=mixed,errors=remount-ro)

The kernel image in /boot/ directory was used and the /boot directory is in /dev/sda2, a hard disk.
I’m almost sure but is this possible because (my system used UEFI for booting, I can see /boot/efi/EFI/ directory)
the UEFI firmware has file system driver and could open the disk partition and used the kernel image to boot
the UEFI firmware detected the disk (using SCSI driver?) and edited the system hardware information (here maybe ACPI table) and passed it to linux kernel.
Is my understanding correct?

Thanks in advance.
Regards,
Chan Kim

_______________________________________________
Kernelnewbies mailing list
Kernelnewbies@xxxxxxxxxxxxxxxxx
https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies