In one embodiment, a method and apparatus for stack walking a call stack associated with mixed code, by interleaving a native stack walking process with a managed stack walking process. Mixed code comprises at least one managed instruction and at least one native instruction, and the call stack comprises at least one managed frame and at least one native frame. The managed frames being associated with the managed instructions, and the native frames being associated with native instructions. The method comprises acts of performing a managed stack walk on the call stack, a native stack walk on native frames of the call stack. In a further embodiment, handling indirect jumps during a native stack walk, and in another embodiment, detecting validity of a memory address.