cast_kern
#define cast_kern(ptr) /* nop for bpf prog. emitted by LLVM */
#define cast_kern(ptr) bpf_addr_space_cast(ptr, 0, 1)
#define cast_kern(ptr) /* nop for user space */
#define cast_kern(ptr) /* nop for bpf prog. emitted by LLVM */
#define cast_kern(ptr) bpf_addr_space_cast(ptr, 0, 1)
#define cast_kern(ptr) /* nop for user space */