On MDT side, the S_ENCRYPTED flag is set when setting the encryption context, because internally, ldiskfs sets the LDISKFS_ENCRYPT_FL flag on the on-disk inode when the encryption.c xattr is being set (along with the LUSTRE_ENCRYPT_FL flag in the LMA).

On OST side, the LUSTRE_ENCRYPT_FL flag in the LMA is also set. But this does not lead to the LDISKFS_ENCRYPT_FL flag being set on the on-disk inode.

So we would need to improve OSD layer’s behavior. By adding a dumb encryption context on OST objects when the LUSTRE_ENCRYPT_FL flag gets set in the LMA, ldiskfs would internally set the LDISKFS_ENCRYPT_FL flag on the on-disk inode.