fix: bootloader changes (#4073)

* Bootloader changes:

	-> GRUB: Support for UKI
		- Disable 10_linux or breaks at kernel updates
		- Create 09_custom entry
	-> rEFInd:
		- Remove fallback entry similar to other bootloaders
		- With UKI still one dead entry can be hidden with DEL key
	-> All bootloaders:
		- Default to UKI on if supported, if using no UKI and /efi
		Causes systemd boot to not load, because it needs a XTLDRBOOT part
		Safer default for modern setups and simpler sec boot compat

* Add new models

* Modify based on grub-2.14-rc1 -> No need to use chainload
Thanks to codefiles for the heads-up

* Simplify has_uki_support

* Tab

* checks

archinstall/lib/installer.py

@@ -1325,6 +1325,7 @@ class Installer:
 		boot_partition: PartitionModification,
 		root: PartitionModification | LvmVolume,
 		efi_partition: PartitionModification | None,
+		uki_enabled: bool = False,
 		bootloader_removable: bool = False,
 	) -> None:
 		debug('Installing grub bootloader')
@@ -1396,6 +1397,37 @@ class Installer:
 			except SysCallError as err:
 				raise DiskError(f'Failed to install GRUB boot on {boot_partition.dev_path}: {err}')
 
+		# Add custom UKI entries if enabled
+		if uki_enabled and SysInfo.has_uefi() and efi_partition:
+			custom_entries = self.target / 'etc/grub.d/09_custom'
+			entries_content = (
+				'#!/bin/sh\n'
+				'exec tail -n +3 $0\n'
+				'# This file provides UKI (Unified Kernel Image) boot entries.\n'
+				'# Generated by archinstall. Do not modify the exec tail line above.\n'
+				'# Custom entries can be added below.\n\n'
+			)
+
+			uki_entries = []
+			for kernel in self.kernels:
+				entry = textwrap.dedent(
+					f"""
+					menuentry "Arch Linux ({kernel}) UKI" {{
+						uki /EFI/Linux/arch-{kernel}.efi
+					}}
+					"""
+				)
+				uki_entries.append(entry)
+
+			entries_content += '\n'.join(uki_entries)
+			custom_entries.write_text(entries_content)
+			custom_entries.chmod(0o755)
+
+			# Disable 10_linux to prevent broken entries on kernel updates
+			linux_script = self.target / 'etc/grub.d/10_linux'
+			if linux_script.exists():
+				linux_script.chmod(0o644)
+
 		try:
 			self.arch_chroot(
 				f'grub-mkconfig -o {boot_dir}/grub/grub.cfg',
@@ -1669,29 +1701,28 @@ class Installer:
 		kernel_params = ' '.join(self._get_kernel_params(root))
 
 		for kernel in self.kernels:
-			for variant in ('', '-fallback'):
-				if uki_enabled:
-					entry = f'"Arch Linux ({kernel}{variant}) UKI" "{kernel_params}"'
-				else:
-					if boot_on_root:
-						# Kernels are in /boot subdirectory of root filesystem
-						if hasattr(root, 'btrfs_subvols') and root.btrfs_subvols:
-							# Root is btrfs with subvolume, find the root subvolume
-							root_subvol = next((sv for sv in root.btrfs_subvols if sv.is_root()), None)
-							if root_subvol:
-								subvol_name = root_subvol.name
-								initrd_path = f'initrd={subvol_name}\\boot\\initramfs-{kernel}{variant}.img'
-							else:
-								initrd_path = f'initrd=\\boot\\initramfs-{kernel}{variant}.img'
+			if uki_enabled:
+				entry = f'"Arch Linux ({kernel}) UKI" "{kernel_params}"'
+			else:
+				if boot_on_root:
+					# Kernels are in /boot subdirectory of root filesystem
+					if hasattr(root, 'btrfs_subvols') and root.btrfs_subvols:
+						# Root is btrfs with subvolume, find the root subvolume
+						root_subvol = next((sv for sv in root.btrfs_subvols if sv.is_root()), None)
+						if root_subvol:
+							subvol_name = root_subvol.name
+							initrd_path = f'initrd={subvol_name}\\boot\\initramfs-{kernel}.img'
 						else:
-							# Root without btrfs subvolume
-							initrd_path = f'initrd=\\boot\\initramfs-{kernel}{variant}.img'
+							initrd_path = f'initrd=\\boot\\initramfs-{kernel}.img'
 					else:
-						# Kernels are at root of their partition (ESP or separate boot partition)
-						initrd_path = f'initrd=\\initramfs-{kernel}{variant}.img'
-					entry = f'"Arch Linux ({kernel}{variant})" "{kernel_params} {initrd_path}"'
+						# Root without btrfs subvolume
+						initrd_path = f'initrd=\\boot\\initramfs-{kernel}.img'
+				else:
+					# Kernels are at root of their partition (ESP or separate boot partition)
+					initrd_path = f'initrd=\\initramfs-{kernel}.img'
+				entry = f'"Arch Linux ({kernel})" "{kernel_params} {initrd_path}"'
 
-				config_contents.append(entry)
+			config_contents.append(entry)
 
 		config_path.write_text('\n'.join(config_contents) + '\n')
 
@@ -1823,7 +1854,7 @@ class Installer:
 			case Bootloader.Systemd:
 				self._add_systemd_bootloader(boot_partition, root, efi_partition, uki_enabled)
 			case Bootloader.Grub:
-				self._add_grub_bootloader(boot_partition, root, efi_partition, bootloader_removable)
+				self._add_grub_bootloader(boot_partition, root, efi_partition, uki_enabled, bootloader_removable)
 			case Bootloader.Efistub:
 				self._add_efistub_bootloader(boot_partition, root, uki_enabled)
 			case Bootloader.Limine:

archinstall/lib/models/bootloader.py

@@ -20,11 +20,7 @@ class Bootloader(Enum):
 	Refind = 'Refind'
 
 	def has_uki_support(self) -> bool:
-		match self:
-			case Bootloader.Efistub | Bootloader.Limine | Bootloader.Systemd | Bootloader.Refind:
-				return True
-			case _:
-				return False
+		return self != Bootloader.NO_BOOTLOADER
 
 	def has_removable_support(self) -> bool:
 		match self:
@@ -82,7 +78,8 @@ class BootloaderConfiguration:
 	def get_default(cls) -> BootloaderConfiguration:
 		bootloader = Bootloader.get_default()
 		removable = SysInfo.has_uefi() and bootloader.has_removable_support()
-		return cls(bootloader=bootloader, uki=False, removable=removable)
+		uki = SysInfo.has_uefi() and bootloader.has_uki_support()
+		return cls(bootloader=bootloader, uki=uki, removable=removable)
 
 	def preview(self) -> str:
 		text = f'{tr("Bootloader")}: {self.bootloader.value}'