sys_openat2
asmlinkage long sys_openat2(int dfd, const char __user *filename,
__SYSCALL(__NR_openat2, sys_openat2)
__SYSCALL(__NR_openat2, sys_openat2)
fd = sys_openat2(AT_FDCWD, ".", &how);
int sys_openat2(int dfd, const char *path, struct open_how *how);
fd = sys_openat2(AT_FDCWD, path, &test->how);
fd = sys_openat2(afd, victim_path, &how);
fd = sys_openat2(dfd, test->path, &test->how);