On Mon, Jun 07, 2021 at 10:09:44AM +0300, Efraim Flashner wrote:
> Upstream u-boot support was merged days ago³ so we should be able to add
> support to our u-boot package soon-ish™.

I added u-boot-sifive-unmatched, although Vagrant pointed out that I may
be missing opensbi as an input. I haven't had a chance to test it yet.

> Where I'm at right now:
> Downloading using the daemon (builtin:download) fails currently, it says
> it doesn't have permissions to open-file to write downloaded files to
> the store.
> I haven't built anything using the bootstrap binaries to see if they
> actually work yet.

I've had some time to play with these parts. I tried the qemu-binfmt
emulation on my Guix System machine and I was able to start building out
the packages while emulating riscv64-linux, so that's a good sign.

As for writing to the store goes, I believe it's a permissions issue
somewhere. With some help on IRC I modified the downloading code and
wrote out some files using the builtin:download function to a file in my
home directory. I also used a minimal reproducer to write a file to the
store:

scheme@(guile-user)> (use-modules (guix gexp)(guix store)(guix monad-repl))
scheme@(guile-user)> ,enter-store-monad
store-monad@(guile-user) [1]> (text-file "foo" "Hello!\n")
$2 = "/gnu/store/r4bq7f7aikj0dlzjcl2cjgal5wvdhvk1-foo"

(ins)efraim@unmatched:~$ cat /gnu/store/r4bq7f7aikj0dlzjcl2cjgal5wvdhvk1-foo
Hello!

So that works. Could it be that I messed up creating the guixbuild
users? I copy/pasted from the manual, command history shows me I ran:
root@unmatched:/home/efraim# for i in $(seq -w 1 10);   do     useradd -g guixbuild -G guixbuild                       -d /var/empty -s $(which nologin)               -c "Guix build user $i" --system                guixbuilder$i;   done


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Efraim Flashner   <efraim@flashner.co.il>   אפרים פלשנר
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