4 ms·

OneFileLinux: A 20MB Alpine metadistro that fits into the ESP

92 points by lproven 2y ago

AstroJetson 2y ago
Slight difference between EFI and ESP. Works on my EFI laptop, my ESP32 board wasn’t having it.
- gtirloni 2y ago
  https://en.wikipedia.org/wiki/EFI_system_partition https://en.wikipedia.org/wiki/EFI_system_partition
  - lproven 2y ago
    Yup, that. In hindsight "fitting into" a microcontroller does also work, sort of...
- yonatan8070 2y ago
  In this context ESP = EFI System Partition
  - lproven 2y ago
    [OP here] That is correct -- thanks. I did not think it was ambiguous in context. Silly me.
- galangalalgol 2y ago
  Given the specs on an esp32, or stm32 for that matter, a usable desktop should really be possible. The amiga1k didn't have anything but page protection from its mmu, and many microcontrollers can do that. The web experience would be... different, but a lot should work fine.
  - rcxdude 2y ago
    Yeah, you could certainly make an older OS work quite nicely on such hardware. You can even cram Linux into such devices, but it's not going to give a smooth interface
    - galangalalgol 2y ago
      I didn't think you could get modern kernels to work eithout an mmu that supports virtual memory? In any case linux seems a bit heavy. Something based off redox might work, it has a small code base at least, but it would be a lot of work.
- pantalaimon 2y ago
  You’re joking but you can run Linux on the ESP32-S3 https://github.com/ESP32DE/Boot-Linux-ESP32S3-Playground https://github.com/ESP32DE/Boot-Linux-ESP32S3-Playground
- taneq 2y ago
  Ohhhhh! Yeah the "ESP can be up to 4GB" had me totally lost. Like, no, the ones we use have 4MB of flash.
ksp-atlas 2y ago
I made this exact thing like 2 years ago except with a custom busybox based environment, huh It worked by building the system into the initramfs, then using a kernel feature to basically bake the initramfs into the kernel image, and then using efistub to make the kernel bootable
- ravenstine 2y ago
  Do you happen to remember what that kernel feature was called? I did something very similar, and it'd be cool to have one fewer file to deal with.
  - candiddevmike 2y ago
    UKI, maybe? https://github.com/uapi-group/specifications/blob/main/specs/unified_kernel_image.md https://github.com/uapi-group/specifications/blob/main/specs...
- westurner 2y ago
  Efistub Kernel docs > admin-guide/efistub: https://docs.kernel.org/admin-guide/efi-stub.html https://docs.kernel.org/admin-guide/efi-stub.html : > Like most boot loaders, the EFI stub allows the user to specify multiple initrd files using the “initrd=” option. This is the only EFI stub-specific command line parameter, everything else is passed to the kernel when it boots Arch Wiki > EFISTUB: https://wiki.archlinux.org/title/EFISTUB https://wiki.archlinux.org/title/EFISTUB : > The option is enabled by default on Arch Linux kernels, or if compiling the kernel one can activate it by setting CONFIG_EFI_STUB=y in the Kernel configuration. eaut/efistub is a script for managing signed efistubs: https://github.com/eaut/efistub https://github.com/eaut/efistub ... Systemrescuecd can be PXE booted (netbooted) from tftpd managed by Cobbler or Foreman. From "Booting Linux off of Google Drive" https://news.ycombinator.com/item?id=40853770#40859485 https://news.ycombinator.com/item?id=40853770#40859485 re: signing and iPXE Ventoy boots via grub/efi but there are blobs: https://news.ycombinator.com/item?id=40619822#40620279 https://news.ycombinator.com/item?id=40619822#40620279 "Ask HN: Where can I find a primer on how computers boot?" https://news.ycombinator.com/item?id=35230852 https://news.ycombinator.com/item?id=35230852 systemd-boot and grub support booting to efistubs "Migrate from systemd-boot to EFISTUB" https://www.reddit.com/r/archlinux/comments/14jt8yv/migrate_from_systemdboot_to_efistub/ https://www.reddit.com/r/archlinux/comments/14jt8yv/migrate_... : > You don't "disable" systemd-boot, you just don't run it. Or you can delete the boot entry for it with efibootmgr if you want. You also don't need to "set up" EFISTUB, the stub is already built into the Arch kernels, so they're already bootable. So all you need to do is make a boot entry in your UEFI using efibootmgr with the correct kernel parameters, most likely the same ones you used for systemd-boot. Fedora > Changes/Unified_Kernel_Support_Phase_2 > Switch_an_existing_install_to_use_UKIs: https://fedoraproject.org/wiki/Changes/Unified_Kernel_Support_Phase_2#Switch_an_existing_install_to_use_UKIs https://fedoraproject.org/wiki/Changes/Unified_Kernel_Suppor... : dnf install virt-firmware uki-direct kernel-uki-virt kernel-bootcfg --show https://github.com/spxak1/weywot/blob/main/guides/fedora_systemd-boot_Unified_kernel.md https://github.com/spxak1/weywot/blob/main/guides/fedora_sys... : sudo dracut -fvM --uefi --hostonly-cmdline --kernel-cmdline "root=UUID=b6b8fa59-92cc-4d03-8d8f-d66dab76d433 ro rootflags=subvol=root resume=UUID=fb661671-97dc-45db-b720-062acdcf095e rhgb quiet mitigations =off" - "No more boot loader: Please use the kernel instead" https://news.ycombinator.com/item?id=40907933 https://news.ycombinator.com/item?id=40907933 Gentoo wiki > EFI_stub https://wiki.gentoo.org/wiki/EFI_stub https://wiki.gentoo.org/wiki/EFI_stub : > It is recommended to always have a backup kernel. If a bootmanager like grub is already installed, it should not be uninstalled, because grub can boot a stub kernel just like a normal kernel. A second possibility is to work with an additional UEFI entry. Before installing a new kernel, the current one can be copied from /efi/EFI/example/ to /efi/EFI/backup. [And then efibootmgr]
shzhdbi09gv8ioi 2y ago
Slightly misleading title "20 MB Linux.EFI" ... Download 25MB ... Leads to 26MB download file ... Holds a compressed partition of 209 MB.
- _joel 2y ago
  I don't think it's that misleading, bzImage and the like are comressed, so...
  - galangalalgol 2y ago
    It is a little surprising given alpine images are regularly less than 10MB.
    - ale42 2y ago
      They are compressed too, right?
      - galangalalgol 2y ago
        I'm not sure. The only thing in there besides busy box and apj is the kernel and a bunch of text files.
lproven 2y ago
This looks interesting and I can certainly see a use for it. It'd be very handy as a fallback/rescue system, and that includes for Windows as well as Linux. Shame it's not been updated in so long.
sp1rit 2y ago
The ESP is just a FAT-32 partition, so its capable of being up to 4GB (by default). At 4GB you can probably store most linux distributions on the ESP, so the title makes it less impressive than it is.
- boricj 2y ago
  Technically the ESP doesn't have to be a FAT32 partition. UEFI has file system drivers installable at runtime [1], so you could have an ESP partition that isn't FAT32... assuming that the file system driver for it is loaded. UEFI implementations must have built-in support for FAT per the specification, but you'd need to slipstream any extra EFI drivers into your platform's firmware that are required to get to the ESP. I think that ESP partitions formatted as HFS+ were a thing on Intel Macs, but I've never had one to try it out. [1] rEFInd's website lists a bunch of available file system drivers: https://www.rodsbooks.com/refind/drivers.html#selecting https://www.rodsbooks.com/refind/drivers.html#selecting
  - NekkoDroid 2y ago
    IIRC FAT32 is the only that needs to be supported for a valid UEFI implementation. So to actually have something like that alpine image work for most it does need to be limited to that. There are also standalone EFI drivers that can be loaded by other means: https://archlinux.org/packages/extra/any/efifs/ https://archlinux.org/packages/extra/any/efifs/ (e.g. systemd-boot loads these if they are installed to `<esp>/EFI/systemd/drivers/`)
    - actionfromafar 2y ago
      I guess one could do something like put a large ext4 file image on the FAT32 partition and mount that from within Linux.
- zimbatm 2y ago
  Except most ESP partitions I have seen are in the 200MB range. So now you're asking your users not only to bless the EFI loader, but also to resize their ESP, and most likely system partition.
NekkoDroid 2y ago
Fun fact: you can easily create your own USIs (Unified system image), which basically does the same (is the same concept?), with mkosi[1]. [1]: https://overhead.neocities.org/blog/build-usi-mkosi/ https://overhead.neocities.org/blog/build-usi-mkosi/ Another example: https://swsnr.de/archlinux-rescue-image-with-mkosi/ https://swsnr.de/archlinux-rescue-image-with-mkosi/
- lproven 2y ago
  AIUI -- correct me if I am wrong -- this is intended for building UKI images to boot a conventional distro from a root partition, so it's not the planned usage to construct a standalone distro from it?
  - NekkoDroid 2y ago
    Generally building UKIs is the intended output, but the only thing that tells systemd to pivot into an actual root is if it boots into the `initrd.target` unit, which by default it does when `/etc/initrd-release` exists. Other than that USIs and UKIs aren't very different. To answer the question if its planned: yes. It is officially supported to build USIs, just its not an explicit output format since its just a slightly different UKI (from a systemd perspective).
lproven 2y ago
[OP here] Source here: https://github.com/zhovner/OneFileLinux/ https://github.com/zhovner/OneFileLinux/ This is crying out for an update, IMHO.
candiddevmike 2y ago
If your looking for something similar only for distributions like Debian, Ubuntu, Fedora etc checkout EtchaOS: https://etcha.dev/etchaos https://etcha.dev/etchaos
- lproven 2y ago
  Not really the same thing or even comparable, AFAICS, no. EtchaOS is for building a custom immutable distro, but it is a conventional distro with a root partition. This is a distro which doesn't have a root partition. It doesn't just boot from the UEFI ESP: it fits entirely into it, with no other partitions.
  - candiddevmike 2y ago
    In EtchaOS, the entire distro is contained within the initrd file. So I guess it's technically two files, kernel and initrd, but still similar. UKIs and similar are nice but don't play well with secure boot (unless you setup your own signing) and BIOS boot.
deleted 2y ago
[deleted]
omneity 2y ago
And here I was secretly hoping someone managed to make a minimal MMU-free linux distro to run on ESP32. This is the last I've heard of such an effort: https://www.cnx-software.com/2019/12/03/western-digital-risc-v-linux-busybox-boot-sipeed-maix-go-board/ https://www.cnx-software.com/2019/12/03/western-digital-risc...
- programmeruser 2y ago
  There's a version for the ESP32-S3: https://github.com/ESP32DE/Boot-Linux-ESP32S3-Playground https://github.com/ESP32DE/Boot-Linux-ESP32S3-Playground
  - omneity 2y ago
    That's just incredible! Thank you so much for sharing :)

92 points by lproven 2y ago

AstroJetson 2y ago

Slight difference between EFI and ESP. Works on my EFI laptop, my ESP32 board wasn’t having it.

gtirloni 2y ago
https://en.wikipedia.org/wiki/EFI_system_partition https://en.wikipedia.org/wiki/EFI_system_partition
- lproven 2y ago
  Yup, that. In hindsight "fitting into" a microcontroller does also work, sort of...
yonatan8070 2y ago
In this context ESP = EFI System Partition
- lproven 2y ago
  [OP here] That is correct -- thanks. I did not think it was ambiguous in context. Silly me.
galangalalgol 2y ago
Given the specs on an esp32, or stm32 for that matter, a usable desktop should really be possible. The amiga1k didn't have anything but page protection from its mmu, and many microcontrollers can do that. The web experience would be... different, but a lot should work fine.
- rcxdude 2y ago
  Yeah, you could certainly make an older OS work quite nicely on such hardware. You can even cram Linux into such devices, but it's not going to give a smooth interface
  - galangalalgol 2y ago
    I didn't think you could get modern kernels to work eithout an mmu that supports virtual memory? In any case linux seems a bit heavy. Something based off redox might work, it has a small code base at least, but it would be a lot of work.
pantalaimon 2y ago
You’re joking but you can run Linux on the ESP32-S3 https://github.com/ESP32DE/Boot-Linux-ESP32S3-Playground https://github.com/ESP32DE/Boot-Linux-ESP32S3-Playground
taneq 2y ago
Ohhhhh! Yeah the "ESP can be up to 4GB" had me totally lost. Like, no, the ones we use have 4MB of flash.

ksp-atlas 2y ago

I made this exact thing like 2 years ago except with a custom busybox based environment, huh It worked by building the system into the initramfs, then using a kernel feature to basically bake the initramfs into the kernel image, and then using efistub to make the kernel bootable

ravenstine 2y ago
Do you happen to remember what that kernel feature was called? I did something very similar, and it'd be cool to have one fewer file to deal with.
- candiddevmike 2y ago
  UKI, maybe? https://github.com/uapi-group/specifications/blob/main/specs/unified_kernel_image.md https://github.com/uapi-group/specifications/blob/main/specs...
westurner 2y ago
Efistub Kernel docs > admin-guide/efistub: https://docs.kernel.org/admin-guide/efi-stub.html https://docs.kernel.org/admin-guide/efi-stub.html : > Like most boot loaders, the EFI stub allows the user to specify multiple initrd files using the “initrd=” option. This is the only EFI stub-specific command line parameter, everything else is passed to the kernel when it boots Arch Wiki > EFISTUB: https://wiki.archlinux.org/title/EFISTUB https://wiki.archlinux.org/title/EFISTUB : > The option is enabled by default on Arch Linux kernels, or if compiling the kernel one can activate it by setting CONFIG_EFI_STUB=y in the Kernel configuration. eaut/efistub is a script for managing signed efistubs: https://github.com/eaut/efistub https://github.com/eaut/efistub ... Systemrescuecd can be PXE booted (netbooted) from tftpd managed by Cobbler or Foreman. From "Booting Linux off of Google Drive" https://news.ycombinator.com/item?id=40853770#40859485 https://news.ycombinator.com/item?id=40853770#40859485 re: signing and iPXE Ventoy boots via grub/efi but there are blobs: https://news.ycombinator.com/item?id=40619822#40620279 https://news.ycombinator.com/item?id=40619822#40620279 "Ask HN: Where can I find a primer on how computers boot?" https://news.ycombinator.com/item?id=35230852 https://news.ycombinator.com/item?id=35230852 systemd-boot and grub support booting to efistubs "Migrate from systemd-boot to EFISTUB" https://www.reddit.com/r/archlinux/comments/14jt8yv/migrate_from_systemdboot_to_efistub/ https://www.reddit.com/r/archlinux/comments/14jt8yv/migrate_... : > You don't "disable" systemd-boot, you just don't run it. Or you can delete the boot entry for it with efibootmgr if you want. You also don't need to "set up" EFISTUB, the stub is already built into the Arch kernels, so they're already bootable. So all you need to do is make a boot entry in your UEFI using efibootmgr with the correct kernel parameters, most likely the same ones you used for systemd-boot. Fedora > Changes/Unified_Kernel_Support_Phase_2 > Switch_an_existing_install_to_use_UKIs: https://fedoraproject.org/wiki/Changes/Unified_Kernel_Support_Phase_2#Switch_an_existing_install_to_use_UKIs https://fedoraproject.org/wiki/Changes/Unified_Kernel_Suppor... : dnf install virt-firmware uki-direct kernel-uki-virt kernel-bootcfg --show https://github.com/spxak1/weywot/blob/main/guides/fedora_systemd-boot_Unified_kernel.md https://github.com/spxak1/weywot/blob/main/guides/fedora_sys... : sudo dracut -fvM --uefi --hostonly-cmdline --kernel-cmdline "root=UUID=b6b8fa59-92cc-4d03-8d8f-d66dab76d433 ro rootflags=subvol=root resume=UUID=fb661671-97dc-45db-b720-062acdcf095e rhgb quiet mitigations =off" - "No more boot loader: Please use the kernel instead" https://news.ycombinator.com/item?id=40907933 https://news.ycombinator.com/item?id=40907933 Gentoo wiki > EFI_stub https://wiki.gentoo.org/wiki/EFI_stub https://wiki.gentoo.org/wiki/EFI_stub : > It is recommended to always have a backup kernel. If a bootmanager like grub is already installed, it should not be uninstalled, because grub can boot a stub kernel just like a normal kernel. A second possibility is to work with an additional UEFI entry. Before installing a new kernel, the current one can be copied from /efi/EFI/example/ to /efi/EFI/backup. [And then efibootmgr]

shzhdbi09gv8ioi 2y ago

Slightly misleading title "20 MB Linux.EFI" ... Download 25MB ... Leads to 26MB download file ... Holds a compressed partition of 209 MB.

_joel 2y ago
I don't think it's that misleading, bzImage and the like are comressed, so...
- galangalalgol 2y ago
  It is a little surprising given alpine images are regularly less than 10MB.
  - ale42 2y ago
    They are compressed too, right?
    - galangalalgol 2y ago
      I'm not sure. The only thing in there besides busy box and apj is the kernel and a bunch of text files.

lproven 2y ago

This looks interesting and I can certainly see a use for it. It'd be very handy as a fallback/rescue system, and that includes for Windows as well as Linux. Shame it's not been updated in so long.

sp1rit 2y ago

The ESP is just a FAT-32 partition, so its capable of being up to 4GB (by default). At 4GB you can probably store most linux distributions on the ESP, so the title makes it less impressive than it is.

boricj 2y ago
Technically the ESP doesn't have to be a FAT32 partition. UEFI has file system drivers installable at runtime [1], so you could have an ESP partition that isn't FAT32... assuming that the file system driver for it is loaded. UEFI implementations must have built-in support for FAT per the specification, but you'd need to slipstream any extra EFI drivers into your platform's firmware that are required to get to the ESP. I think that ESP partitions formatted as HFS+ were a thing on Intel Macs, but I've never had one to try it out. [1] rEFInd's website lists a bunch of available file system drivers: https://www.rodsbooks.com/refind/drivers.html#selecting https://www.rodsbooks.com/refind/drivers.html#selecting
- NekkoDroid 2y ago
  IIRC FAT32 is the only that needs to be supported for a valid UEFI implementation. So to actually have something like that alpine image work for most it does need to be limited to that. There are also standalone EFI drivers that can be loaded by other means: https://archlinux.org/packages/extra/any/efifs/ https://archlinux.org/packages/extra/any/efifs/ (e.g. systemd-boot loads these if they are installed to `<esp>/EFI/systemd/drivers/`)
  - actionfromafar 2y ago
    I guess one could do something like put a large ext4 file image on the FAT32 partition and mount that from within Linux.
zimbatm 2y ago
Except most ESP partitions I have seen are in the 200MB range. So now you're asking your users not only to bless the EFI loader, but also to resize their ESP, and most likely system partition.

NekkoDroid 2y ago

Fun fact: you can easily create your own USIs (Unified system image), which basically does the same (is the same concept?), with mkosi[1]. [1]: https://overhead.neocities.org/blog/build-usi-mkosi/ https://overhead.neocities.org/blog/build-usi-mkosi/ Another example: https://swsnr.de/archlinux-rescue-image-with-mkosi/ https://swsnr.de/archlinux-rescue-image-with-mkosi/

lproven 2y ago
AIUI -- correct me if I am wrong -- this is intended for building UKI images to boot a conventional distro from a root partition, so it's not the planned usage to construct a standalone distro from it?
- NekkoDroid 2y ago
  Generally building UKIs is the intended output, but the only thing that tells systemd to pivot into an actual root is if it boots into the `initrd.target` unit, which by default it does when `/etc/initrd-release` exists. Other than that USIs and UKIs aren't very different. To answer the question if its planned: yes. It is officially supported to build USIs, just its not an explicit output format since its just a slightly different UKI (from a systemd perspective).

lproven 2y ago

[OP here] Source here: https://github.com/zhovner/OneFileLinux/ https://github.com/zhovner/OneFileLinux/ This is crying out for an update, IMHO.

candiddevmike 2y ago

If your looking for something similar only for distributions like Debian, Ubuntu, Fedora etc checkout EtchaOS: https://etcha.dev/etchaos https://etcha.dev/etchaos

lproven 2y ago
Not really the same thing or even comparable, AFAICS, no. EtchaOS is for building a custom immutable distro, but it is a conventional distro with a root partition. This is a distro which doesn't have a root partition. It doesn't just boot from the UEFI ESP: it fits entirely into it, with no other partitions.
- candiddevmike 2y ago
  In EtchaOS, the entire distro is contained within the initrd file. So I guess it's technically two files, kernel and initrd, but still similar. UKIs and similar are nice but don't play well with secure boot (unless you setup your own signing) and BIOS boot.

deleted 2y ago

[deleted]

omneity 2y ago

And here I was secretly hoping someone managed to make a minimal MMU-free linux distro to run on ESP32. This is the last I've heard of such an effort: https://www.cnx-software.com/2019/12/03/western-digital-risc-v-linux-busybox-boot-sipeed-maix-go-board/ https://www.cnx-software.com/2019/12/03/western-digital-risc...

programmeruser 2y ago
There's a version for the ESP32-S3: https://github.com/ESP32DE/Boot-Linux-ESP32S3-Playground https://github.com/ESP32DE/Boot-Linux-ESP32S3-Playground
- omneity 2y ago
  That's just incredible! Thank you so much for sharing :)