selftests/powerpc: Put the test in a separate process group

Allows us to kill the test and any children it has spawned.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

tools/testing/selftests/powerpc/harness.c

@@ -30,12 +30,15 @@ int run_test(int (test_function)(void), char *name)
 
 	pid = fork();
 	if (pid == 0) {
+		setpgid(0, 0);
 		exit(test_function());
 	} else if (pid == -1) {
 		perror("fork");
 		return 1;
 	}
 
+	setpgid(pid, pid);
+
 	/* Wake us up in timeout seconds */
 	alarm(TIMEOUT);
 	terminated = false;
@@ -50,17 +53,20 @@ int run_test(int (test_function)(void), char *name)
 
 		if (terminated) {
 			printf("!! force killing %s\n", name);
-			kill(pid, SIGKILL);
+			kill(-pid, SIGKILL);
 			return 1;
 		} else {
 			printf("!! killing %s\n", name);
-			kill(pid, SIGTERM);
+			kill(-pid, SIGTERM);
 			terminated = true;
 			alarm(KILL_TIMEOUT);
 			goto wait;
 		}
 	}
 
+	/* Kill anything else in the process group that is still running */
+	kill(-pid, SIGTERM);
+
 	if (WIFEXITED(status))
 		status = WEXITSTATUS(status);
 	else {