The 27-year-old Irving, who must still complete the NFL's new six-day player intake process, last played in the NFL in 2018. He announced in March 2019 that he was quitting football.
Irving's announcement came shortly after the NFL suspended him indefinitely for violating its substance-abuse policy for a third time in as many years. He revealed his decision in an Instagram video where he appeared to be smoking marijuana, saying he was walking away due to the NFL's restrictive policies on the substance.
But with players no longer being tested for marijuana use under the new collective bargaining agreement, Irving wanted to return to the league. The NFL reinstated Irving on Friday from his indefinite ban.
Irving, an undrafted free agent out of Iowa State, made his NFL debut with the Cowboys in 2015. He recorded 56 total tackles, 12.5 sacks, five forced fumbles and one fumble recovery in 37 career games with Dallas from 2015-18.
Meanwhile, the Raiders are coming off their bye week and could use the extra help on their defensive front. Las Vegas is tied for 29th in the league with seven team sacks. Defensive end Maxx Crosby leads the Raiders with four sacks.