Hello Joel Fernandes (Google),
The patch 233ad92edbea: "pidfd: add polling selftests" from Apr 30, 2019, leads to the following static checker warning:
./tools/testing/selftests/pidfd/pidfd_test.c:522 test_pidfd_poll_leader_exit() error: uninitialized symbol 'ret'.
./tools/testing/selftests/pidfd/pidfd_test.c 485 static void test_pidfd_poll_leader_exit(int use_waitpid) 486 { 487 int pid, pidfd = 0; 488 int status, ret; 489 time_t prog_start = time(NULL); 490 const char *test_name = "pidfd_poll check for premature notification on non-empty" 491 "group leader exit"; 492 493 child_exit_secs = mmap(NULL, sizeof *child_exit_secs, PROT_READ | PROT_WRITE, 494 MAP_SHARED | MAP_ANONYMOUS, -1, 0); 495 496 if (child_exit_secs == MAP_FAILED) 497 ksft_exit_fail_msg("%s test: mmap failed (errno %d)\n", 498 test_name, errno); 499 500 ksft_print_msg("Parent: pid: %d\n", getpid()); 501 pid = pidfd_clone(CLONE_PIDFD, &pidfd, child_poll_leader_exit_test); 502 if (pid < 0) 503 ksft_exit_fail_msg("%s test: pidfd_clone failed (ret %d, errno %d)\n", 504 test_name, pid, errno); 505 506 ksft_print_msg("Parent: Waiting for Child (%d) to complete.\n", pid); 507 508 if (use_waitpid) { 509 ret = waitpid(pid, &status, 0); 510 if (ret == -1) 511 ksft_print_msg("Parent: error\n"); 512 } else { 513 /* 514 * This sleep tests for the case where if the child exits, and is in 515 * EXIT_ZOMBIE, but the thread group leader is non-empty, then the poll 516 * doesn't prematurely return even though there are active threads 517 */ 518 sleep(1); 519 poll_pidfd(test_name, pidfd);
"ret" is not initialized on this path.
520 } 521 522 if (ret == pid) ^^^ 523 ksft_print_msg("Parent: Child process waited for.\n"); 524 525 time_t since_child_exit = time(NULL) - *child_exit_secs; 526 527 ksft_print_msg("Time since child exit: %lu\n", since_child_exit);
regards, dan carpenter