GPG Hangs When Private Keys are Accessed

Question

I like to sign my git commits with my PGP key, so I was quite alarmed when I went to git commit -S but instead of prompting for my PGP key passphrase, git just started hanging. I haven't made a change to my GPG setup in several months and have made many commits since then with no problem. Additionally, when I attempt to view my private keys with gpg -K, gpg hangs. However, when I run gpg -k to view my public keys, it returns the list like normal. Hopefully someone will have some idea of what is causing this problem and how to fix it.

Answer 1

I came across this exact issue (OSX Sierra 10.12.6, gpg/GnuPG 2.2.5)

Commands that would hang:

gpg -K # --list-secret-keys
gpg -d # --decrypt
gpg --edit-key
gpgconf --kill gpg-agent

My solution was the same as mentioned by John above (ie. kill gpg-agent) as most other methods on how-can-i-restart-gpg-agent would also hang.

# Solution    
pkill -9 gpg-agent

Then for signing git commits I set the tty env as mentioned by cas above and also at gpg-failed-to-sign-commit-object.

export GPG_TTY=$(tty)

Answer 2

$ ps aux | grep -E "gpg-agent"
alper  28970   0.0   92436   3284   15:31 0:00 /usr/bin/gpg-agent --supervised

Here output variable contains 28970.

---

from subprocess import Popen, PIPE
import signal

def kill_process_by_name(process_name):
    p1 = Popen(["ps", "auxww"], stdout=PIPE)
    p2 = Popen(["grep", "-E", process_name], stdin=p1.stdout, stdout=PIPE)
    p1.stdout.close()  # noqa
    p3 = Popen(["awk", "{print $2}"], stdin=p2.stdout, stdout=PIPE)
    p2.stdout.close()
    output = p3.communicate()[0].decode("utf-8").strip()
    lines = output.splitlines()  # awk may return more than one pid number
    for pid in lines:
        if pid.isnumeric():
            os.kill(int(pid), signal.SIGKILL)