systemd-boot: allow splitting entries to xbootldr part #226692

colemickens · 2023-04-17T19:05:51Z

Description of changes

This allows systemd-boot to be installed to the ESP, while NixOS loader entries and files can exist on the extended boot loader partition.

This is particularly useful on dual boot systems, where Windows is allowed to install first and establishes the ESP partition. Often times it chooses a very small size that is prohibitive with regards to NixOS's boot files.

This PR adds an option that allows the user to redirect the loader entries/files to (what is hopefully their) extended boot loader partition.

Note, I use this PR on systems where this extra partition is in use, AND systems where it is not, so I am not worried about regression(s).

~
❯ exa --tree --level=3 /efi
/efi
├── EFI
│  ├── Boot
│  │  └── bootx64.efi
│  ├── Microsoft
│  │  ├── Boot
│  │  └── Recovery
│  └── systemd
│     └── systemd-bootx64.efi
├── loader
│  ├── loader.conf
│  └── random-seed
└── System Volume Information

~
❯ exa --tree --level=3 /boot
/boot
├── EFI
│  ├── Linux
│  └── nixos
│     ├── 5y4wli77bnnjfz76bfran03gb6012y6d-initrd-linux-6.1.23-initrd.efi
│     ├── ady11nphd2fx30yqchq6j2jgf645waw3-linux-6.1.24-bzImage.efi
│     ├── gf7hymimhfqn7qxjh08j04jzjp18djbm-initrd-linux-6.1.23-initrd.efi
│     ├── mnayyi1fzaa4g46lb1qg46r0hjwj15fm-initrd-linux-6.1.24-initrd.efi
│     ├── qsp0g4wa01hlw4g8q4rwqbwk3kybv3z1-initrd-linux-6.1.24-initrd.efi
│     ├── xbf2az1nsckrpshiwccdmjwy2jp8hjzi-initrd-linux-6.1.23-initrd.efi
│     └── z79mf6afiz0ywr8zxbv56s13mbd8mz2h-linux-6.1.23-bzImage.efi
└── loader
   ├── entries
   │  ├── nixos-generation-89-specialisation-legacyboot.conf
   │  ├── nixos-generation-89.conf
   │  ├── nixos-generation-90-specialisation-legacyboot.conf
   │  ├── nixos-generation-90.conf
   │  ├── nixos-generation-91-specialisation-legacyboot.conf
   │  ├── nixos-generation-91.conf
   │  ├── nixos-generation-92-specialisation-legacyboot.conf
   │  └── nixos-generation-92.conf
   └── entries.srel

Things done

colemickens · 2023-04-17T19:06:42Z

I'm partly getting this out there, possibly still too late, just to make sure it's a known use-case regarding bootspec... I'm trying to get caught back up to NixOS-world...

RaitoBezarius · 2023-04-20T11:57:56Z

I believe XBOOTLDR is already supported by bootspec.

colemickens · 2023-05-03T16:38:24Z

I will likely abandon this whenever this is resolved on lanzaboot: nix-community/lanzaboote#173

sdht0 · 2023-08-17T13:28:35Z

Hi, what is needed to get this PR over the finish line?

My EFI partition is only around 100MB thanks to Windows, and in a virtual machine, I can see that NixOS already needs 90MB from two kernels.

colemickens · 2023-08-17T13:29:33Z

@sdht0 as I noted in the linked lanzaboote issue you can use this to workaround for now:

config = {
  fileSystems = {
     # ..
      "/efi/EFI/Linux" = { device = "/boot/EFI/Linux"; options = ["bind"];};
      "/efi/EFI/nixos" = { device = "/boot/EFI/nixos"; options = ["bind"];};
    };
}

sdht0 · 2023-08-17T13:33:47Z

Ah neat, thanks.

ElvishJerricco · 2023-09-19T02:39:02Z

I think I'd prefer to have naming closer to the spec stuff; like efiSysMountPoint isn't quite what ESP stands for, but at least its close. So entriesMountPoint should probably be something more like xbootMountPoint.

colemickens · 2023-09-19T18:14:50Z

@ElvishJerricco rebased, and updated per your suggestion. It's just a rename but I can end-to-end test this. My only machine with xboot part is now using lanzaboote.

nixos-discourse · 2023-09-24T16:37:53Z

This pull request has been mentioned on NixOS Discourse. There might be relevant details there:

https://discourse.nixos.org/t/manually-partitioned-graphical-installation-of-nixos-doesnt-boot-efi-system-partition-configured-incorrectly/33419/3

sdht0

I did not manage to get the bind mount trick working (entries were not appearing in the bootloader), so I used an override instead by copying the two files from nixpkgs:

  disabledModules = [ "system/boot/loader/systemd-boot/systemd-boot.nix" ];
  imports = [ ./systemd-boot.nix ];

sdht0 · 2023-09-30T17:37:53Z

nixos/modules/system/boot/loader/systemd-boot/systemd-boot-builder.py

@@ -81,7 +81,7 @@ def copy_from_profile(profile: Optional[str], generation: int, specialisation: O
    store_dir = os.path.basename(os.path.dirname(store_file_path))
    efi_file_path = "/efi/nixos/%s-%s.efi" % (store_dir, suffix)
    if not dry_run:
-        copy_if_not_exists(store_file_path, "@efiSysMountPoint@%s" % (efi_file_path))
+        copy_if_not_exists(store_file_path, "@entriesMountPoint@%s" % (efi_file_path))


s/entriesMountPoint/xbootMountPoint/ everywhere no?

sdht0 · 2023-09-30T17:39:00Z

nixos/modules/system/boot/loader/systemd-boot/systemd-boot-builder.py


    subprocess.check_call("@copyExtraFiles@")

    # Since fat32 provides little recovery facilities after a crash,
    # it can leave the system in an unbootable state, when a crash/outage
    # happens shortly after an update. To decrease the likelihood of this
    # event sync the efi filesystem after each update.
-    rc = libc.syncfs(os.open("@efiSysMountPoint@", os.O_RDONLY))
+    rc = libc.syncfs(os.open("@entriesMountPoint@", os.O_RDONLY))


Needs a second syncfs command:

if "@xbootMountPoint@" != "@efiSysMountPoint@": rc = libc.syncfs(os.open("@efiSysMountPoint@", os.O_RDONLY)) if rc != 0: print("could not sync @efiSysMountPoint@: {}".format(os.strerror(rc)), file=sys.stderr)

sdht0 · 2023-09-30T17:41:03Z

nixos/modules/system/boot/loader/systemd-boot/systemd-boot-builder.py

@@ -286,8 +286,8 @@ def main() -> None:
                print("updating systemd-boot from %s to %s" % (installed_version, available_version))
                subprocess.check_call(["@systemd@/bin/bootctl", "--esp-path=@efiSysMountPoint@"] + bootctl_flags + ["update"])


Add an explicit boot-path?

if "@xbootMountPoint@" != "@efiSysMountPoint@": bootctl_flags.append("--boot-path=@xbootMountPoint@")

colemickens · 2023-09-30T22:14:41Z

@sdht0 do you want to take this over maybe? You left a good review and I clearly didn't test this when I pushed it last. It might be good for you to take it over, if you want. If you want, just open a new one and CC me on it and I'll close this one in favor of it.

sdht0 · 2023-10-01T18:39:12Z

I don't mind. I'll prepare the PR in the next couple of weeks, after I've added the ability to cleanup entries on a config change.

Is there anything else I need to do to get it actually merged? This PR has been open for a while.

colemickens · 2023-10-01T18:48:48Z

I think I'd want another review from @ElvishJerricco, but I'm not really aware of anything else that should block it.

Also, if @RaitoBezarius can weigh in on whether or not XBOOTLDR is officially supported by bootspec, or not, and whether or not that should affect the usefulness or mergability of this PR. I'm not sure I can speak to that.

ElvishJerricco · 2023-10-02T05:33:59Z

I guess one other noteworthy thing is that extraFiles and extraEntries probably should be adapted to copy to the XBOOTLDR instead of the ESP.

As a future a note, a good followup PR would be one that enables copying drivers to the $esp/EFI/systemd/drivers/ to support more file system types for XBOOTLDR (and whatever else drivers can do), along with packaging efifs for FS driver implementations.

RaitoBezarius · 2023-10-02T11:06:48Z

Also, if @RaitoBezarius can weigh in on whether or not XBOOTLDR is officially supported by bootspec, or not, and whether or not that should affect the usefulness or mergability of this PR. I'm not sure I can speak to that.

Per se, XBOOTLDR is not formalized inside bootspec in its version 1, but you can always add it as an extension and we can document it.

I don't think anything except the builder needs the information about the entries mountpoint.

Drivers will also be necessary if the target entry mountpoint is not a supported FS for UEFI.

RaitoBezarius · 2023-10-02T11:07:13Z

I also think it's extremely important for that PR to have tests.

sdht0 · 2023-10-10T15:17:58Z

New PR is at #260241

colemickens · 2023-10-11T06:39:14Z

Thanks for continuing, fixing and improving this, @sdht0, especially the tests. Closing in favor of #260241

colemickens requested a review from dasJ as a code owner April 17, 2023 19:05

github-actions bot added 6.topic: nixos Issues or PRs affecting NixOS modules, or package usability issues specific to NixOS 8.has: module (update) This PR changes an existing module in `nixos/` labels Apr 17, 2023

ofborg bot added 10.rebuild-darwin: 0 This PR does not cause any packages to rebuild on Darwin 10.rebuild-linux: 1-10 labels Apr 17, 2023

colemickens mentioned this pull request May 3, 2023

XBOOTLDR support nix-community/lanzaboote#173

Open

nikstur mentioned this pull request Aug 6, 2023

nixos/systemd-boot: Add mirroredBoots #246897

Closed

12 tasks

systemd-boot: add xbootMountPoint option to place entries on xboot part

035eeaa

colemickens force-pushed the xbootloader branch from 09a67b1 to 035eeaa Compare September 19, 2023 18:14

sdht0 reviewed Sep 30, 2023

View reviewed changes

sdht0 mentioned this pull request Oct 10, 2023

nixos/systemd-boot: Add support for an XBOOTLDR partition #260241

Closed

12 tasks

colemickens closed this Oct 11, 2023

sdht0 mentioned this pull request Nov 6, 2023

[RFC 0165] Bootspec v2 NixOS/rfcs#165

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colemickens deleted the xbootloader branch February 17, 2024 04:08

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systemd-boot: allow splitting entries to xbootldr part #226692

systemd-boot: allow splitting entries to xbootldr part #226692

colemickens commented Apr 17, 2023

colemickens commented Apr 17, 2023

RaitoBezarius commented Apr 20, 2023

colemickens commented May 3, 2023

sdht0 commented Aug 17, 2023

colemickens commented Aug 17, 2023

sdht0 commented Aug 17, 2023

ElvishJerricco commented Sep 19, 2023

colemickens commented Sep 19, 2023

nixos-discourse commented Sep 24, 2023

sdht0 left a comment

sdht0 Sep 30, 2023

sdht0 Sep 30, 2023

sdht0 Sep 30, 2023

colemickens commented Sep 30, 2023

sdht0 commented Oct 1, 2023

colemickens commented Oct 1, 2023

ElvishJerricco commented Oct 2, 2023

RaitoBezarius commented Oct 2, 2023

RaitoBezarius commented Oct 2, 2023

sdht0 commented Oct 10, 2023

colemickens commented Oct 11, 2023

		@@ -286,8 +286,8 @@ def main() -> None:
		print("updating systemd-boot from %s to %s" % (installed_version, available_version))
		subprocess.check_call(["@systemd@/bin/bootctl", "--esp-path=@efiSysMountPoint@"] + bootctl_flags + ["update"])

systemd-boot: allow splitting entries to xbootldr part #226692

systemd-boot: allow splitting entries to xbootldr part #226692

Conversation

colemickens commented Apr 17, 2023

Description of changes

Things done

colemickens commented Apr 17, 2023

RaitoBezarius commented Apr 20, 2023

colemickens commented May 3, 2023

sdht0 commented Aug 17, 2023

colemickens commented Aug 17, 2023

sdht0 commented Aug 17, 2023

ElvishJerricco commented Sep 19, 2023

colemickens commented Sep 19, 2023

nixos-discourse commented Sep 24, 2023

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