The 36-year-old, who has represented Chelsea, West Ham United and Newcastle United in his career, is still wanted by Fulham.
The Fulham man has been linked with a summer switch to Glasgow Rangers.
Nottingham Forest recently hired former Rangers trio Mark Warburton, David Weir and Frank McParland after their departures from Ibrox last month.
Glasgow Rangers manager Mark Warburton has already admitted he is looking to bring midfielders to Ibrox, while QPR boss Holloway is described as a fan.
Fulham held Sunderland to a goalless draw at the Stadium of Light in the fourth round of the FA Cup on Saturday.
Ryan Tunnicliffe has returned to Fulham from fellow Championship outfit Blackburn Rovers.
Larnell Cole and Ryan Tunnicliffe are reportedly looking to leave Fulham, having been demoted to the development squad six months after joining.
Former Manchester United youngster Ryan Tunnicliffe has failed to impress during a loan spell at Wigan Athletic, and his parent club don't want him back.
Larnell Cole has joined Ryan Tunnicliffe in being told he can leave Fulham on a loan deal for the rest of the season.
Reports claim Fulham's Ryan Tunnicliffe is set to leave the club on loan.