$ git clone --recursive https://github.com/armbian/u-boot-sun50i
Cloning into 'u-boot-sun50i'...
remote: Counting objects: 104, done.
remote: Total 104 (delta 0), reused 0 (delta 0), pack-reused 104
Receiving objects: 100% (104/104), 15.69 KiB | 0 bytes/s, done.
Resolving deltas: 100% (60/60), done.
Submodule 'arm-trusted-firmware' (https://github.com/apritzel/arm-trusted-firmware.git) registered for path 'arm-trusted-firmware'
Submodule 'u-boot' (https://github.com/apritzel/u-boot.git) registered for path 'u-boot'
Cloning into '/home/samuel/u-boot-sun50i/arm-trusted-firmware'...
remote: Counting objects: 17522, done.
remote: Total 17522 (delta 0), reused 0 (delta 0), pack-reused 17522
Receiving objects: 100% (17522/17522), 7.72 MiB | 0 bytes/s, done.
Resolving deltas: 100% (10761/10761), done.
Cloning into '/home/samuel/u-boot-sun50i/u-boot'...
remote: Counting objects: 460786, done.
remote: Total 460786 (delta 0), reused 0 (delta 0), pack-reused 460785
Receiving objects: 100% (460786/460786), 101.46 MiB | 41.18 MiB/s, done.
Resolving deltas: 100% (375772/375772), done.
Submodule path 'arm-trusted-firmware': checked out 'cd7fa4893dd204e419a8403a8d1dc1c295e3d698'
error: Server does not allow request for unadvertised object a5ff48698e4bf96246c730072f95f448575c8b11
Fetched in submodule path 'u-boot', but it did not contain a5ff48698e4bf96246c730072f95f448575c8b11. Direct fetching of that commit failed.
$
Commit a5ff48698e4bf96246c730072f95f448575c8b11 is in https://github.com/ehoutsma/u-boot, but https://github.com/armbian/u-boot-sun50i/commit/d93f68f62302dd4f988a8a448b23b12cbf99ded1 switched to a fork that does not contain that commit. Browsing on GitHub (https://github.com/apritzel/u-boot/tree/a5ff48698e4bf96246c730072f95f448575c8b11) only happens to work because of the way forks are implemented, using a shared repository. Would it be possible to switch .gitmodules back to the repository that contains the referenced commit?