Encryption can't find master key, please check the keyring is loaded

[Stefano Pisani]

Hello everyone,
After upgrading MySQL Enterprise from 8.0.32 to 8.4.7 on Red Hat Enterprise Linux 8, I’m now getting the following error whenever I try to access encrypted InnoDB tables:

ERROR 3185 (HY000): Encryption can't find master key, please check the keyring is loaded

The mysqld service starts without issues, but any query against tables that use tablespace encryption (TDE) fails with the error above.What I have already checked:The same keyring plugin that worked on 8.0.32 is configured (keyring_file, keyring_encrypted_file, or keyring_oci – same as before)
The keyring file is present in the expected location with correct ownership/permissions (owned by mysql:mysql, 660)
early-plugin-load is correctly set in my.cnf
No errors related to the keyring appear in the MySQL error log during startup

Is there any change in master key handling or keyring migration procedure between MySQL 8.0 and 8.4 that I might have missed when TDE is enabled? Do I need to rotate or re-import the master encryption key after this kind of major version upgrade?Any help or pointers would be greatly appreciated!

Thank you in advance!