This bug rendered a few of our systems inoperable after in ran out of semaphore space. The bug is described here:
⚓ T6947 unnamed semaphore leak on AIX (gnupg.org)

We reverted to gnupg2-2.2.35-1.ppc to bypass the issue.
Here's the test proof:

]9010435@malva:~> oslevel -s
7200-05-07-2346
[]9010435@malva:~> rpm -qa gnupg2
gnupg2-2.4.3-1.ppc
[]9010435@malva:~> ipcs -ras | grep 9010435
[]9010435@malva:~> /opt/freeware/bin/g13
Warning: using insecure memory!
g13: invalid command (there is no implicit command)
[]9010435@malva:~> ipcs -ras | grep 9010435
s         - 0xffffffff --ra-ra-ra-  9010435    staff  9010435    staff     1 14:56:46 14:56:46    -    -
[]9010435@malva:~> /opt/freeware/bin/g13
Warning: using insecure memory!
g13: invalid command (there is no implicit command)
[]9010435@malva:~> ipcs -ras | grep 9010435
s         - 0xffffffff --ra-ra-ra-  9010435    staff  9010435    staff     1 14:56:58 14:56:58    -    -
s         - 0xffffffff --ra-ra-ra-  9010435    staff  9010435    staff     1 14:56:46 14:56:46    -    -

Probably a good idea to remove 2.4 from the list until resolved, as it renders the system inoperable.

For those who encounter this issue or are using gpg then you may want to check your semaphore counts. I think we were around a million when it finally froze up.

You can remove them with ipcrm -r -u if you catch it in time.

Thank you for reporting.
We will update gnupg and npth package. 
Once it's done , we will update on this discussion.

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Ranjit Ranjan
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