I've found a situation where "got fetch" hangs. Here are instructions to
reproduce. I'm using got build at the main branch (commit 45e6b2f4).

Summary: clone a repo with two commits, then try to fetch from a repo
with only the first commit.

Detailed steps:

##
## Run on remote host "h0":
##

cd /home/falsifian/tmp
# create a git repo "a" with one commit
mkdir a; cd a; git init; touch f; git add f; git commit -m initial
# clone it
cd ..
git clone a b
# add a commit to a not present in b
cd a; touch g; git add g; git commit -m a

##
## Run on client
##

got clone ssh://h0/home/falsifian/tmp/a
cat >> a.git/got.conf <<EOF
remote "other" {
        server h0
        protocol ssh
        repository "/home/falsifian/tmp/b"
        branch { "master" }
}
EOF
got co a.git
cd a
got fetch -vvv other

Here's the end of the output of got fetch:
debug2: exec request accepted on channel 0
got-fetch-pack: readpkt: 257:   0583166b49b60158176b9ec4a8daa84cff79fdde HEAD[0x00]multi_ack thin-pack side-band side-band-64k ofs-delta shallow deepen-since deepen-not deepen-relative no-progress include-tag multi_ack_detailed symref=HEAD:refs/heads/master object-format=sha1 agent=git/2.37.3[0x0a]
got-fetch-pack: server capabilities: multi_ack thin-pack side-band side-band-64k ofs-delta shallow deepen-since deepen-not deepen-relative no-progress include-tag multi_ack_detailed symref=HEAD:refs/heads/master object-format=sha1 agent=git/2.37.3
got-fetch-pack: my capabilities: side-band-64k ofs-delta agent=got/0.84-current
got-fetch-pack: readpkt: 59:    0583166b49b60158176b9ec4a8daa84cff79fdde refs/heads/master[0x0a]
got-fetch-pack: refs/heads/master will be fetched
got-fetch-pack: remote: 0583166b49b60158176b9ec4a8daa84cff79fdde
got-fetch-pack: local:  37817389a7fe22fb330be5ec56e2b616e9b5824b
got-fetch-pack: readpkt: 66:    0583166b49b60158176b9ec4a8daa84cff79fdde refs/remotes/origin/HEAD[0x0a]
got-fetch-pack: ignoring refs/remotes/origin/HEAD
got-fetch-pack: readpkt: 68:    0583166b49b60158176b9ec4a8daa84cff79fdde refs/remotes/origin/master[0x0a]
got-fetch-pack: ignoring refs/remotes/origin/master
got-fetch-pack: readpkt: 0:
got-fetch-pack: writepkt: 0061: want 0583166b49b60158176b9ec4a8daa84cff79fdde side-band-64k ofs-delta agent=got/0.84-current[0x0a]
got-fetch-pack: writepkt: 0000
got-fetch-pack: writepkt: 0032: have 37817389a7fe22fb330be5ec56e2b616e9b5824b[0x0a]
got-fetch-pack: writepkt: 0032: have 37817389a7fe22fb330be5ec56e2b616e9b5824b[0x0a]
got-fetch-pack: writepkt: 0032: have 37817389a7fe22fb330be5ec56e2b616e9b5824b[0x0a]

-- 
James