Diddy and Drake haven't just squashed their beef, they've built a bonafide friendship ... and that's why Diddy made the surprise appearance at his North Carolina concert.
Sources close to the rappers tell us they hang out frequently since hashing out their legendary Miami fight with a phone call a year ago.
Diddy's been holding a boot camp in Pennsylvania for his upcoming Bad Boy Family Reunion tour -- and we're told Diddy took a private jet to Carolina after Drake hooked up tickets for him and his crew.
As for why Diddy sat with the normies -- one source says Diddy wanted to experience the show like a fan ... and BFF, of course.
The bromance was even on display at the VMAs.