In May 2003, at 17 years of age, he made his debut in a Torneo Descentralizado match against Atlético Universidad, but he did not play regularly for Juan Flores was still the first choice for goalkeeper.

After his loan ended in December, he signed a two-year contract with Sporting Cristal, where he disputed the goalkeeper spot with Manuel Heredia after the injury and departure from the club of Erick Delgado.

Carvallo became the starting goalkeeper for the whole year, at the end of which Universitario defeated Real Garcilaso in the Torneo Descentralizado finals after three games.

In 2015, to the surprise of many and despite the good level shown by him, Universitario signed another goalkeeper in Raúl Fernández, from MLS club FC Dallas.

After Fernández's arrival, and in spite of manager Roberto Challe's decision to rotate between both goalkeepers, Carvallo stopped playing regularly which made his departure imminent.

[6] In June 2023, after a brawl following the 1–0 victory against Gimnasia de La Plata for the 2023 Copa Sudamericana, Carvallo was sent off and subsequently suspended for 8 matches in all continental club competitions.

[7] At the end of the season, with him as vice-captain and one of the team's leaders, Universitario won the Liga 1, giving Carvallo his second national title, after defeating Alianza Lima in the finals.

He made his full national team debut for Peru in September 2007, when he entered the match as a second-half substitute in a 2-0 victory over Bolivia in Lima.