I just tried to upgrade my GuixSD x86_64 system and it failed saying:

grafting '/gnu/store/z7qr06vxqkqr983sarh50d4p8m45b51z-icedtea-3.1.0-doc'
-> '/gnu/store/0minmdl1fgh96xakpgp73mwh4qcjvvs4-icedtea-3.1.0-doc'...
grafting '/gnu/store/3ldp9zinsnzr9jmacrjk1j4y39cydrpf-icedtea-3.1.0-jdk'
-> '/gnu/store/gfj39lzp301pf2ny51c5lz48mykaf07r-icedtea-3.1.0-jdk'...
grafting '/gnu/store/c23hqrmzsd4k9a13nyrmvmimqf5pfjbn-icedtea-3.1.0' ->
'/gnu/store/g5bn1xbaqs4h30x4n0ggrhabh11winwf-icedtea-3.1.0'...
suspicious ownership or permission on
`/gnu/store/0minmdl1fgh96xakpgp73mwh4qcjvvs4-icedtea-3.1.0-doc';
rejecting this build output
cannot build derivation
`/gnu/store/m2p785lr8m6j4qzkrly05w1nxxiavkjx-profile.drv': 1
dependencies couldn't be built

I updated icedtea successfully using the --no-grafts option.  Is this
the sort of thing I should bring up or just ignore?

Also, is a default of requiring root permission to write a file to a
thumb drive a feature or a bug?

-Ethan Day