For my Intel Pentium G2120, `lshw -class cpu` and `dmidecode -t processor` both claim only one core is enabled on my dual-core Intel Pentium G2120. This is despite ‘All’ being enabled in the UEFI settings for cores enabled.
This is apparently just because lshw and dmidecode are not smart enough. `lscpu` tells it how it really is:
CPU(s): 2 On-line CPU(s) list: 0,1