thank you for all these details Pascal. good week-end to all. Le ven. 16 déc. 2022 à 16:48, Pascal Hambourg <[email protected]> a écrit :
> On 16/12/2022 at 15:32, Pascal wrote: > > does this new summary, which takes into account the previous feedback, > seem > > "better" to you ? > > Yes, better. > > > Is the second remark² correct ? > > I guess so, as long as the required drivers are embedded in the core > image and the drive can be read via the BIOS/UEFI. But your diagram of > EFI boot still shows in inside the ESP. > > > is the boot sector of the image directly/readily accessible (eg. editable > > with hexedit) in the boot sector ? > > Not sure I understand what you mean. The MBR is accessible just like any > other sector. > > > INTEL/MBR GPT > > PARTITIONING PARTITIONING > > ┌─────────────────────┬─────────────────────┐ > > │MBR 1/3 │MBR 1/3 │ > > │POST-MBR-GAP 2/3 │ │ > > │┌───────────────────┐│┌───────────────────┐│ > > ││PART │││PART BIOS-BOOT 2/3 ││ > > ││/boot/grub/ 3/3 ││└───────────────────┘│ > > BIOS ││... ││┌───────────────────┐│ > > BOOT ││ │││PART ││ > > ││ │││/boot/grub/ 3/3 ││ > > ││ │││... ││ > > │└───────────────────┘│└───────────────────┘│ > > ├─────────────────────┼─────────────────────┤ > > Note that this is only the standard layout. Other layouts are possible > such as: > - a primary boot loader installed in the MBR and chainloads GRUB boot > image installed in a partition boot sector (PBR) > - core image installed in a Btrfs filesystem reserved boot area > - core image installed as a file /boot/grub/i386-pc/core.img (using > block lists, unreliable) > > > # in BIOS mode : > > - 1/3 BIOS load and run GRUB boot loader located in the MBR > > "GRUB boot image" would be more accurate. "GRUB boot loader" is the > whole GRUB, not only the boot sector part. > > > - 2/3 GRUB boot loader load and run GRUB core image stored in > > POST-MBR-GAP (INTEL/MBR) or on BIOS-BOOT partition (GTP)¹ > > GPT. > > > - 3/3 GRUB core image find and mount the GRUB folder², load > configuration > > etc.. > > GRUB does not really mount filesystems. It just reads them. > s/folder/directory/. There is no such thing as "folder" in usual > filesystems. > > > > > # in UEFI mode : > > - 1/2 UEFI³ load and run GRUB boot loader located on ESP⁴ > > "GRUB core image" would be more accurate. "GRUB boot loader" is the > whole GRUB (including modules in /boot/grub), not only the core image. >
