uml: definitively kill subprocesses on panic

	ptrace(PTRACE_TRACEME, 0, 0, 0);

	init_new_thread_signals();

	signal(SIGTERM, SIG_DFL);

	err = set_interval();

	if (err)

		panic("userspace_tramp - setting timer failed, errno = %d\n",

void os_dump_core(void)

{

	int pid;

	signal(SIGSEGV, SIG_DFL);

	/*

	 * We are about to SIGTERM this entire process group to ensure that

	 * nothing is around to run after the kernel exits.  The

	 * kernel wants to abort, not die through SIGTERM, so we

	 * ignore it here.

	 */

	signal(SIGTERM, SIG_IGN);

	kill(0, SIGTERM);

	/*

	 * Most of the other processes associated with this UML are

	 * likely sTopped, so give them a SIGCONT so they see the

	 * SIGTERM.

	 */

	kill(0, SIGCONT);

	/*

	 * Now, having sent signals to everyone but us, make sure they

	 * die by ptrace.  Processes can survive what's been done to

	 * them so far - the mechanism I understand is receiving a

	 * SIGSEGV and segfaulting immediately upon return.  There is

	 * always a SIGSEGV pending, and (I'm guessing) signals are

	 * processed in numeric order so the SIGTERM (signal 15 vs

	 * SIGSEGV being signal 11) is never handled.

	 *

	 * Run a waitpid loop until we get some kind of error.

	 * Hopefully, it's ECHILD, but there's not a lot we can do if

	 * it's something else.  Tell os_kill_ptraced_process not to

	 * wait for the child to report its death because there's

	 * nothing reasonable to do if that fails.

	 */

	while ((pid = waitpid(-1, NULL, WNOHANG)) > 0)

		os_kill_ptraced_process(pid, 0);

	abort();

}