| 2 May 2023 |
 @elvishjerricco:matrix.org | * But that's super lame because we don't need to do that for boot.growPartition, which I was hoping to implement in systemd-initrd via repart | 21:24:14 |
| @elvishjerricco:matrix.org | but growPartition just assumes you've set fileSystems."/".device to something with a number at the end that can be dropped to get to the disk | 21:24:49 |
 Arian | well we can still implement that as a compatibiliy hack? | 21:25:31 |
| @elvishjerricco:matrix.org | Yea I guess we can move the number-dropping logic out of shell script and into nix code and set boot.initrd.systemd.repart.device with that | 21:26:05 |
| Arian | exactly | 21:26:17 |
| Arian | having nixos-install call systemd-repart would be nice too.
have nixos-install --flake github:arianvp#mymachine just work would be kinda magical
| 21:26:54 |
| @elvishjerricco:matrix.org | oh that's a cool idea | 21:27:22 |
| Arian | I now do this: https://github.com/arianvp/nixos-stuff/blob/master/configs/utm/install.sh | 21:27:45 |
| @elvishjerricco:matrix.org | So one slightly crazier idea than parsing device file names with nix would be to go nuts with udev | 21:29:05 |
| @elvishjerricco:matrix.org | i.e. set up a udev rule that waits for fileSystems."/".device and creates a /dev/repart-actual-root-node symlink that points to the parent-most device of that device | 21:30:00 |
| @elvishjerricco:matrix.org | oh but that does expect the root partition to at least exist already | 21:30:24 |
| @elvishjerricco:matrix.org | so nevermind | 21:30:27 |
| @elvishjerricco:matrix.org | Arian: Anyway, I think the only other thing we could really do besides a boot.initrd.repart.device option would be to repurpose /sysusr for /nix/store (which is kind of morally correct anyway tbh), and and pull the system's toplevel store path from the init= parameter like we doinnixos-activation.servicein order to find repart definitions. The big advantage here is that the root device would be derived from the backing device of/sysusr/usr(which we would hack up to be derived from/sysusr/nix/store), so that we don't need an explicit device to be set. But that does mean your /nix/store` has to be on a partition on your root disk, and can't be something fancy like a 9p file system or something | 21:36:37 |
| @elvishjerricco:matrix.org | * Arian: Anyway, I think the only other thing we could really do besides a boot.initrd.repart.device option would be to repurpose /sysusr for /nix/store (which is kind of morally correct anyway tbh), and and pull the system's toplevel store path from the init= parameter like we do innixos-activation.servicein order to find repart definitions. The big advantage here is that the root device would be derived from the backing device of/sysusr/usr(which we would hack up to be derived from/sysusr/nix/store), so that we don't need an explicit device to be set. But that does mean your /nix/store\ has to be on a partition on your root disk, and can't be something fancy like a 9p file system or something | 21:37:01 |
| @elvishjerricco:matrix.org | * Arian: Anyway, I think the only other thing we could really do besides a boot.initrd.repart.device option would be to repurpose /sysusr for /nix/store (which is kind of morally correct anyway tbh), and and pull the system's toplevel store path from the init= parameter like we do innixos-activation.servicein order to find repart definitions. The big advantage here is that the root device would be derived from the backing device of/sysusr/usr(which we would hack up to be derived from/sysusr/nix/store), so that we don't need an explicit device to be set. But that does mean your /nix/store has to be on a partition on your root disk, and can't be something fancy like a 9p file system or something | 21:37:11 |
| Arian | if only we replaced /nix/store with /usr/store | 21:37:28 |
| Arian | dreams | 21:37:31 |
| @elvishjerricco:matrix.org | yea... | 21:37:38 |
| @elvishjerricco:matrix.org | So I dunno which of those two things to do. boot.initrd.repart.device, or /sysusr/nix/store + "your store has to be on your root disk" | 21:38:43 |
| @elvishjerricco:matrix.org | I'm leaning towards the former personally | 21:39:53 |
| @elvishjerricco:matrix.org | oh the other thing is that something like boot.initrd.repart.device is only needed if the root partition doesn't already exist. | 21:42:10 |
| @elvishjerricco:matrix.org | If it does, we really can just wait for /sysroot to be mounted and let it get the backing device from that itself (though, unless we wait for nixos-activation.service, we do still have to find a way to point it at the right definitions files) | 21:43:24 |
| @elvishjerricco:matrix.org | Every time I think about this problem I just confuse myself more and more with all the possibilities and all the problems... | 21:44:02 |
| Arian | how about we upstream a commit to systemd to support kernel param rd.repart.device=/dev/vda | 21:45:39 |
| Arian | if it's not set it checks for /sysroot | 21:45:59 |
| Arian | otherwise it uses rd.repart.device | 21:46:06 |
| Arian | oh wait that doesn't help | 21:46:32 |
| @elvishjerricco:matrix.org | yea I was about to ask :P | 21:47:23 |
| @elvishjerricco:matrix.org | (of course, that would be sane anyway; just doesn't help our issues) | 21:47:45 |
| Arian | i still dont fully understand how this works upstream | 21:48:55 |
