Talk:EFI system partition

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You must use the root= kernel parameter in order to boot using this method

The sentence "You must use the root= kernel parameter in order to boot using this method" from EFI system partition#Using bind mount has been bugging me for while now. I traced its origins to Special:Diff/277007.

Are there situations where it's possible to omit the root= parameter (not counting boot loader magic since it also passes the parameter to the kernel)?

-- nl6720 (talk) 08:50, 20 April 2019 (UTC)

Preffered mount point for LVM users

In Typical mount points section it is advised to mount esp at /efi if bootloader has drivers to your root file system. But there is no mentioning of root file systems contained in lvm. I had a problem exactly like in this topic. Seems like rEFInd still cannot boot kernels resided inside LVM. It is said that /boot mount point is preferred when directly booting a EFISTUB kernel from UEFI. Should we expand it with "or if you are using LVM"?

Ashark (talk) 05:27, 24 August 2019 (UTC)

It's not limited to just LVM. The boot loader needs drivers for everything that is below the block devices that UEFI provides, be that LVM, RAID, dm-crypt, LUKS, etc, and ending with the file system. The problem is that boot loader capabilities differ. rEFInd only has file system drivers, so it doesn't support anything more complex than a file system on a partition. GRUB has more drivers, so it can access LVM (but not lvmthin(7)), LUKS1 and RAID.
The current sentence is also not entirely correct about needing a driver for the / file system. What it really needs is a file system driver for the volume where /boot is located, that may not necessary be the / file system in case /boot is a separate volume.
At the moment I can't think what to add to EFI system partition#Typical mount points so that it doesn't lose the boot loader examples. Additionally any changes should also be propagated to Arch boot process#Feature comparison and Partitioning#/boot.
-- nl6720 (talk) 06:43, 24 August 2019 (UTC)
Maybe sentenses like this:
mount ESP to /efi and use a boot loader which has a driver of file system which stores /boot. Also bootloader needs drivers for everything that is below the block devices that UEFI provides, be that LVM, RAID, dm-crypt, LUKS, etc.
mount ESP to /boot. This is the preferred method when directly booting a EFISTUB kernel from UEFI or when your bootloader cannot access file system that stores /boot.
Ashark (talk) 07:04, 24 August 2019 (UTC)