Bug#1016873: grub2: enable "http" module for netboot

[Ansgar]

On Mon, 08 Aug 2022 18:54:41 +0200 Ansgar wrote:
> Ubuntu's grub has at least the following changes which seem related:
> 
> +---
> | grub2 (2.06-2ubuntu1) jammy; urgency=medium
> |   * Merge from Debian unstable; remaining changes:
> | [...]
> |     - build-efi-images: Add http to netboot images
> | [...]
> |     - Added patches:
> | [...]
> |       + rhboot-f34-efinet-also-use-the-firmware-acceleration-for-http.patch
> +---

I tried a local build with:
  - http added to NET_MODULES
  - patch suse-add-support-for-UEFI-network-protocols.patch
    (required for the next patch)
  - patch rhboot-f34-efinet-also-use-the-firmware-acceleration-for-http.patch
with the patches from grub2_2.06-2ubuntu7.dsc.

With this grub looks for grub.cfg:

+---
| X.X.X.X - - [08/Aug/2022:22:09:19 +0200] "HEAD /patched/bootx64.efi HTTP/1.1" 200 0 "-" "UefiHttpBoot/1.0"
| X.X.X.X - - [08/Aug/2022:22:09:19 +0200] "GET /patched/bootx64.efi HTTP/1.1" 200 934240 "-" "UefiHttpBoot/1.0"
| X.X.X.X - - [08/Aug/2022:22:09:20 +0200] "GET /patched//grubx64.efi HTTP/1.1" 200 1478656 "-" "UefiHttpBoot/1.0"
| X.X.X.X - - [08/Aug/2022:22:09:20 +0200] "HEAD /grub/x86_64-efi/command.lst HTTP/1.1" 404 0 "-" "UefiHttpBoot/1.0"
| X.X.X.X - - [08/Aug/2022:22:09:20 +0200] "HEAD /grub/x86_64-efi/fs.lst HTTP/1.1" 404 0 "-" "UefiHttpBoot/1.0"
| X.X.X.X - - [08/Aug/2022:22:09:20 +0200] "HEAD /grub/x86_64-efi/crypto.lst HTTP/1.1" 404 0 "-" "UefiHttpBoot/1.0"
| X.X.X.X - - [08/Aug/2022:22:09:20 +0200] "HEAD /grub/x86_64-efi/terminal.lst HTTP/1.1" 404 0 "-" "UefiHttpBoot/1.0"
| X.X.X.X - - [08/Aug/2022:22:09:21 +0200] "HEAD /grub/grub.cfg HTTP/1.1" 200 0 "-" "UefiHttpBoot/1.0"
| X.X.X.X - - [08/Aug/2022:22:09:21 +0200] "GET /grub/grub.cfg HTTP/1.1" 200 779 "-" "UefiHttpBoot/1.0"
+---

It would also be nice if grub searched for grub.cfg in a location
relative to grubx64.efi like shim does for grubx64.efi (shim is
bootx64.efi here).  (And/or DHCP options like pxelinux has[1].)

Ansgar

  [1]: https://wiki.syslinux.org/wiki/index.php?title=PXELINUX#DHCP_options