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

[Chan Kim]

Hello,

In my ubuntu 20.04 machine, 

 

ckim at 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 at ckim-ubuntu:~$ mount | grep boot

/dev/sda2 on /boot/efi type vfat
(rw,relatime,fmask=0077,dmask=0077,codepage=437,iocharset=iso8859-1,shortnam
e=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)

1.	the UEFI firmware has file system driver and could open the disk
partition and used the kernel image to boot
2.	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

 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.kernelnewbies.org/pipermail/kernelnewbies/attachments/20211021/57fe5544/attachment-0001.html>