The Sweden defender has missed the last two matches after being forced off in a 2-2 draw against Leicester City on Boxing Day with a back problem.
The defender has struggled with the issue all season but it flared up against the Foxes, which has meant Eric Bailly has partnered Harry Maguire in the last two matches.
United face rivals City at Old Trafford for a place in April’s final against Tottenham and Solskjaer needs a result to reverse a trend of losing his last three semi-finals with the club.
Asked about the state of the squad, Solskjaer said: ‘Yeah, they’re bright.
‘They had a couple of days of recovery, not recovery, but [it’s been] lighter. We’ve had a couple of days to prepare.
‘Of course, the training is just after we’re talking, so we haven’t had the training this morning. Victor [Lindelof] has been training, he’s been with us. Edinson [Cavani] is suspended.
‘Apart from that we have a very strong squad to choose from.’
Guardiola’s side won the first leg 3-1 at Old Trafford but a Nemanja Matic goal gave the Red Devils victory at the Etihad.
However, City held on and beat Aston Villa 2-1 in the Wembley final.