2 * Copyright (c) 1982, 1986, 1989, 1991, 1993
3 * The Regents of the University of California. All rights reserved.
4 * (c) UNIX System Laboratories, Inc.
5 * All or some portions of this file are derived from material licensed
6 * to the University of California by American Telephone and Telegraph
7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8 * the permission of UNIX System Laboratories, Inc.
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11 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
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19 * may be used to endorse or promote products derived from this software
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25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * @(#)kern_exit.c 8.7 (Berkeley) 2/12/94
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
40 #include "opt_compat.h"
41 #include "opt_kdtrace.h"
42 #include "opt_ktrace.h"
43 #include "opt_procdesc.h"
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/sysproto.h>
48 #include <sys/capability.h>
49 #include <sys/eventhandler.h>
50 #include <sys/kernel.h>
51 #include <sys/malloc.h>
53 #include <sys/mutex.h>
55 #include <sys/procdesc.h>
56 #include <sys/pioctl.h>
60 #include <sys/vmmeter.h>
61 #include <sys/vnode.h>
62 #include <sys/racct.h>
63 #include <sys/resourcevar.h>
65 #include <sys/signalvar.h>
66 #include <sys/sched.h>
68 #include <sys/syscallsubr.h>
69 #include <sys/syslog.h>
70 #include <sys/ptrace.h>
71 #include <sys/acct.h> /* for acct_process() function prototype */
72 #include <sys/filedesc.h>
77 #include <sys/ktrace.h>
80 #include <security/audit/audit.h>
81 #include <security/mac/mac_framework.h>
84 #include <vm/vm_extern.h>
85 #include <vm/vm_param.h>
87 #include <vm/vm_map.h>
88 #include <vm/vm_page.h>
92 #include <sys/dtrace_bsd.h>
93 dtrace_execexit_func_t dtrace_fasttrap_exit;
96 SDT_PROVIDER_DECLARE(proc);
97 SDT_PROBE_DEFINE1(proc, kernel, , exit, "int");
99 /* Hook for NFS teardown procedure. */
100 void (*nlminfo_release_p)(struct proc *p);
103 proc_realparent(struct proc *child)
105 struct proc *p, *parent;
107 sx_assert(&proctree_lock, SX_LOCKED);
108 if ((child->p_treeflag & P_TREE_ORPHANED) == 0) {
109 if (child->p_oppid == 0 ||
110 child->p_pptr->p_pid == child->p_oppid)
111 parent = child->p_pptr;
116 for (p = child; (p->p_treeflag & P_TREE_FIRST_ORPHAN) == 0;) {
117 /* Cannot use LIST_PREV(), since the list head is not known. */
118 p = __containerof(p->p_orphan.le_prev, struct proc,
120 KASSERT((p->p_treeflag & P_TREE_ORPHANED) != 0,
121 ("missing P_ORPHAN %p", p));
123 parent = __containerof(p->p_orphan.le_prev, struct proc,
129 clear_orphan(struct proc *p)
133 sx_assert(&proctree_lock, SA_XLOCKED);
134 if ((p->p_treeflag & P_TREE_ORPHANED) == 0)
136 if ((p->p_treeflag & P_TREE_FIRST_ORPHAN) != 0) {
137 p1 = LIST_NEXT(p, p_orphan);
139 p1->p_treeflag |= P_TREE_FIRST_ORPHAN;
140 p->p_treeflag &= ~P_TREE_FIRST_ORPHAN;
142 LIST_REMOVE(p, p_orphan);
143 p->p_treeflag &= ~P_TREE_ORPHANED;
147 * exit -- death of process.
150 sys_sys_exit(struct thread *td, struct sys_exit_args *uap)
153 exit1(td, W_EXITCODE(uap->rval, 0));
158 * Exit: deallocate address space and other resources, change proc state to
159 * zombie, and unlink proc from allproc and parent's lists. Save exit status
160 * and rusage for wait(). Check for child processes and orphan them.
163 exit1(struct thread *td, int rv)
165 struct proc *p, *nq, *q;
166 struct vnode *ttyvp = NULL;
168 mtx_assert(&Giant, MA_NOTOWNED);
172 * XXX in case we're rebooting we just let init die in order to
173 * work around an unsolved stack overflow seen very late during
174 * shutdown on sparc64 when the gmirror worker process exists.
176 if (p == initproc && rebooting == 0) {
177 printf("init died (signal %d, exit %d)\n",
178 WTERMSIG(rv), WEXITSTATUS(rv));
179 panic("Going nowhere without my init!");
183 * MUST abort all other threads before proceeding past here.
187 * First check if some other thread or external request got
188 * here before us. If so, act appropriately: exit or suspend.
189 * We must ensure that stop requests are handled before we set
192 thread_suspend_check(0);
193 while (p->p_flag & P_HADTHREADS) {
195 * Kill off the other threads. This requires
196 * some co-operation from other parts of the kernel
197 * so it may not be instantaneous. With this state set
198 * any thread entering the kernel from userspace will
199 * thread_exit() in trap(). Any thread attempting to
200 * sleep will return immediately with EINTR or EWOULDBLOCK
201 * which will hopefully force them to back out to userland
202 * freeing resources as they go. Any thread attempting
203 * to return to userland will thread_exit() from userret().
204 * thread_exit() will unsuspend us when the last of the
205 * other threads exits.
206 * If there is already a thread singler after resumption,
207 * calling thread_single will fail; in that case, we just
208 * re-check all suspension request, the thread should
209 * either be suspended there or exit.
211 if (!thread_single(SINGLE_EXIT))
213 * All other activity in this process is now
214 * stopped. Threading support has been turned
219 * Recheck for new stop or suspend requests which
220 * might appear while process lock was dropped in
223 thread_suspend_check(0);
225 KASSERT(p->p_numthreads == 1,
226 ("exit1: proc %p exiting with %d threads", p, p->p_numthreads));
227 racct_sub(p, RACCT_NTHR, 1);
229 * Wakeup anyone in procfs' PIOCWAIT. They should have a hold
230 * on our vmspace, so we should block below until they have
231 * released their reference to us. Note that if they have
232 * requested S_EXIT stops we will block here until they ack
235 _STOPEVENT(p, S_EXIT, rv);
238 * Ignore any pending request to stop due to a stop signal.
239 * Once P_WEXIT is set, future requests will be ignored as
242 p->p_flag &= ~P_STOPPED_SIG;
243 KASSERT(!P_SHOULDSTOP(p), ("exiting process is stopped"));
246 * Note that we are exiting and do another wakeup of anyone in
247 * PIOCWAIT in case they aren't listening for S_EXIT stops or
248 * decided to wait again after we told them we are exiting.
250 p->p_flag |= P_WEXIT;
254 * Wait for any processes that have a hold on our vmspace to
255 * release their reference.
257 while (p->p_lock > 0)
258 msleep(&p->p_lock, &p->p_mtx, PWAIT, "exithold", 0);
260 p->p_xstat = rv; /* Let event handler change exit status */
262 /* Drain the limit callout while we don't have the proc locked */
263 callout_drain(&p->p_limco);
267 * The Sun BSM exit token contains two components: an exit status as
268 * passed to exit(), and a return value to indicate what sort of exit
269 * it was. The exit status is WEXITSTATUS(rv), but it's not clear
270 * what the return value is.
272 AUDIT_ARG_EXIT(WEXITSTATUS(rv), 0);
273 AUDIT_SYSCALL_EXIT(0, td);
276 /* Are we a task leader? */
277 if (p == p->p_leader) {
278 mtx_lock(&ppeers_lock);
282 kern_psignal(q, SIGKILL);
286 while (p->p_peers != NULL)
287 msleep(p, &ppeers_lock, PWAIT, "exit1", 0);
288 mtx_unlock(&ppeers_lock);
292 * Check if any loadable modules need anything done at process exit.
293 * E.g. SYSV IPC stuff
294 * XXX what if one of these generates an error?
296 EVENTHANDLER_INVOKE(process_exit, p);
299 * If parent is waiting for us to exit or exec,
300 * P_PPWAIT is set; we will wakeup the parent below.
303 rv = p->p_xstat; /* Event handler could change exit status */
305 p->p_flag &= ~(P_TRACED | P_PPWAIT | P_PPTRACE);
308 * Stop the real interval timer. If the handler is currently
309 * executing, prevent it from rearming itself and let it finish.
311 if (timevalisset(&p->p_realtimer.it_value) &&
312 callout_stop(&p->p_itcallout) == 0) {
313 timevalclear(&p->p_realtimer.it_interval);
314 msleep(&p->p_itcallout, &p->p_mtx, PWAIT, "ritwait", 0);
315 KASSERT(!timevalisset(&p->p_realtimer.it_value),
316 ("realtime timer is still armed"));
321 * Reset any sigio structures pointing to us as a result of
322 * F_SETOWN with our pid.
324 funsetownlst(&p->p_sigiolst);
327 * If this process has an nlminfo data area (for lockd), release it
329 if (nlminfo_release_p != NULL && p->p_nlminfo != NULL)
330 (*nlminfo_release_p)(p);
333 * Close open files and release open-file table.
339 * If this thread tickled GEOM, we need to wait for the giggling to
340 * stop before we return to userland
342 if (td->td_pflags & TDP_GEOM)
346 * Remove ourself from our leader's peer list and wake our leader.
348 mtx_lock(&ppeers_lock);
349 if (p->p_leader->p_peers) {
351 while (q->p_peers != p)
353 q->p_peers = p->p_peers;
356 mtx_unlock(&ppeers_lock);
360 sx_xlock(&proctree_lock);
361 if (SESS_LEADER(p)) {
362 struct session *sp = p->p_session;
366 * s_ttyp is not zero'd; we use this to indicate that
367 * the session once had a controlling terminal. (for
368 * logging and informational purposes)
379 * Signal foreground pgrp and revoke access to
380 * controlling terminal if it has not been revoked
383 * Because the TTY may have been revoked in the mean
384 * time and could already have a new session associated
385 * with it, make sure we don't send a SIGHUP to a
386 * foreground process group that does not belong to this
392 if (tp->t_session == sp)
393 tty_signal_pgrp(tp, SIGHUP);
398 sx_xunlock(&proctree_lock);
399 if (vn_lock(ttyvp, LK_EXCLUSIVE) == 0) {
400 VOP_REVOKE(ttyvp, REVOKEALL);
401 VOP_UNLOCK(ttyvp, 0);
403 sx_xlock(&proctree_lock);
406 fixjobc(p, p->p_pgrp, 0);
407 sx_xunlock(&proctree_lock);
408 (void)acct_process(td);
410 /* Release the TTY now we've unlocked everything. */
417 * Release reference to text vnode
419 if (p->p_textvp != NULL) {
425 * Release our limits structure.
427 lim_free(p->p_limit);
433 * Remove proc from allproc queue and pidhash chain.
434 * Place onto zombproc. Unlink from parent's child list.
436 sx_xlock(&allproc_lock);
437 LIST_REMOVE(p, p_list);
438 LIST_INSERT_HEAD(&zombproc, p, p_list);
439 LIST_REMOVE(p, p_hash);
440 sx_xunlock(&allproc_lock);
443 * Call machine-dependent code to release any
444 * machine-dependent resources other than the address space.
445 * The address space is released by "vmspace_exitfree(p)" in
450 WITNESS_WARN(WARN_PANIC, NULL, "process (pid %d) exiting", p->p_pid);
453 * Reparent all of our children to init.
455 sx_xlock(&proctree_lock);
456 q = LIST_FIRST(&p->p_children);
457 if (q != NULL) /* only need this if any child is S_ZOMB */
459 for (; q != NULL; q = nq) {
460 nq = LIST_NEXT(q, p_sibling);
462 proc_reparent(q, initproc);
463 q->p_sigparent = SIGCHLD;
465 * Traced processes are killed
466 * since their existence means someone is screwing up.
468 if (q->p_flag & P_TRACED) {
472 * Since q was found on our children list, the
473 * proc_reparent() call moved q to the orphan
474 * list due to present P_TRACED flag. Clear
475 * orphan link for q now while q is locked.
478 q->p_flag &= ~(P_TRACED | P_STOPPED_TRACE);
479 FOREACH_THREAD_IN_PROC(q, temp)
480 temp->td_dbgflags &= ~TDB_SUSPEND;
481 kern_psignal(q, SIGKILL);
487 * Also get rid of our orphans.
489 while ((q = LIST_FIRST(&p->p_orphans)) != NULL) {
495 /* Save exit status. */
499 /* Tell the prison that we are gone. */
500 prison_proc_free(p->p_ucred->cr_prison);
504 * Tell the DTrace fasttrap provider about the exit if it
505 * has declared an interest.
507 if (dtrace_fasttrap_exit)
508 dtrace_fasttrap_exit(p);
512 * Notify interested parties of our demise.
514 KNOTE_LOCKED(&p->p_klist, NOTE_EXIT);
517 int reason = CLD_EXITED;
520 else if (WIFSIGNALED(rv))
522 SDT_PROBE(proc, kernel, , exit, reason, 0, 0, 0, 0);
526 * Just delete all entries in the p_klist. At this point we won't
527 * report any more events, and there are nasty race conditions that
528 * can beat us if we don't.
530 knlist_clear(&p->p_klist, 1);
533 * If this is a process with a descriptor, we may not need to deliver
534 * a signal to the parent. proctree_lock is held over
535 * procdesc_exit() to serialize concurrent calls to close() and
539 if (p->p_procdesc == NULL || procdesc_exit(p)) {
542 * Notify parent that we're gone. If parent has the
543 * PS_NOCLDWAIT flag set, or if the handler is set to SIG_IGN,
544 * notify process 1 instead (and hope it will handle this
547 PROC_LOCK(p->p_pptr);
548 mtx_lock(&p->p_pptr->p_sigacts->ps_mtx);
549 if (p->p_pptr->p_sigacts->ps_flag &
550 (PS_NOCLDWAIT | PS_CLDSIGIGN)) {
553 mtx_unlock(&p->p_pptr->p_sigacts->ps_mtx);
556 proc_reparent(p, initproc);
557 p->p_sigparent = SIGCHLD;
558 PROC_LOCK(p->p_pptr);
561 * Notify parent, so in case he was wait(2)ing or
562 * executing waitpid(2) with our pid, he will
567 mtx_unlock(&p->p_pptr->p_sigacts->ps_mtx);
569 if (p->p_pptr == initproc)
570 kern_psignal(p->p_pptr, SIGCHLD);
571 else if (p->p_sigparent != 0) {
572 if (p->p_sigparent == SIGCHLD)
574 else /* LINUX thread */
575 kern_psignal(p->p_pptr, p->p_sigparent);
579 PROC_LOCK(p->p_pptr);
581 sx_xunlock(&proctree_lock);
584 * The state PRS_ZOMBIE prevents other proesses from sending
585 * signal to the process, to avoid memory leak, we free memory
586 * for signal queue at the time when the state is set.
588 sigqueue_flush(&p->p_sigqueue);
589 sigqueue_flush(&td->td_sigqueue);
592 * We have to wait until after acquiring all locks before
593 * changing p_state. We need to avoid all possible context
594 * switches (including ones from blocking on a mutex) while
595 * marked as a zombie. We also have to set the zombie state
596 * before we release the parent process' proc lock to avoid
597 * a lost wakeup. So, we first call wakeup, then we grab the
598 * sched lock, update the state, and release the parent process'
602 cv_broadcast(&p->p_pwait);
603 sched_exit(p->p_pptr, td);
605 p->p_state = PRS_ZOMBIE;
606 PROC_UNLOCK(p->p_pptr);
609 * Hopefully no one will try to deliver a signal to the process this
612 knlist_destroy(&p->p_klist);
615 * Save our children's rusage information in our exit rusage.
617 ruadd(&p->p_ru, &p->p_rux, &p->p_stats->p_cru, &p->p_crux);
620 * Make sure the scheduler takes this thread out of its tables etc.
621 * This will also release this thread's reference to the ucred.
622 * Other thread parts to release include pcb bits and such.
628 #ifndef _SYS_SYSPROTO_H_
637 sys_abort2(struct thread *td, struct abort2_args *uap)
639 struct proc *p = td->td_proc;
645 * Do it right now so we can log either proper call of abort2(), or
646 * note, that invalid argument was passed. 512 is big enough to
647 * handle 16 arguments' descriptions with additional comments.
649 sb = sbuf_new(NULL, NULL, 512, SBUF_FIXEDLEN);
651 sbuf_printf(sb, "%s(pid %d uid %d) aborted: ",
652 p->p_comm, p->p_pid, td->td_ucred->cr_uid);
654 * Since we can't return from abort2(), send SIGKILL in cases, where
655 * abort2() was called improperly
658 /* Prevent from DoSes from user-space. */
659 if (uap->nargs < 0 || uap->nargs > 16)
661 if (uap->nargs > 0) {
662 if (uap->args == NULL)
664 error = copyin(uap->args, uargs, uap->nargs * sizeof(void *));
669 * Limit size of 'reason' string to 128. Will fit even when
670 * maximal number of arguments was chosen to be logged.
672 if (uap->why != NULL) {
673 error = sbuf_copyin(sb, uap->why, 128);
677 sbuf_printf(sb, "(null)");
679 if (uap->nargs > 0) {
680 sbuf_printf(sb, "(");
681 for (i = 0;i < uap->nargs; i++)
682 sbuf_printf(sb, "%s%p", i == 0 ? "" : ", ", uargs[i]);
683 sbuf_printf(sb, ")");
686 * Final stage: arguments were proper, string has been
687 * successfully copied from userspace, and copying pointers
688 * from user-space succeed.
692 if (sig == SIGKILL) {
694 sbuf_printf(sb, " (Reason text inaccessible)");
698 log(LOG_INFO, "%s", sbuf_data(sb));
700 exit1(td, W_EXITCODE(0, sig));
707 * The dirty work is handled by kern_wait().
710 owait(struct thread *td, struct owait_args *uap __unused)
714 error = kern_wait(td, WAIT_ANY, &status, 0, NULL);
716 td->td_retval[1] = status;
719 #endif /* COMPAT_43 */
722 * The dirty work is handled by kern_wait().
725 sys_wait4(struct thread *td, struct wait4_args *uap)
727 struct rusage ru, *rup;
730 if (uap->rusage != NULL)
734 error = kern_wait(td, uap->pid, &status, uap->options, rup);
735 if (uap->status != NULL && error == 0)
736 error = copyout(&status, uap->status, sizeof(status));
737 if (uap->rusage != NULL && error == 0)
738 error = copyout(&ru, uap->rusage, sizeof(struct rusage));
743 sys_wait6(struct thread *td, struct wait6_args *uap)
745 struct __wrusage wru, *wrup;
751 idtype = uap->idtype;
754 if (uap->wrusage != NULL)
759 if (uap->info != NULL) {
761 bzero(sip, sizeof(*sip));
766 * We expect all callers of wait6() to know about WEXITED and
769 error = kern_wait6(td, idtype, id, &status, uap->options, wrup, sip);
771 if (uap->status != NULL && error == 0)
772 error = copyout(&status, uap->status, sizeof(status));
773 if (uap->wrusage != NULL && error == 0)
774 error = copyout(&wru, uap->wrusage, sizeof(wru));
775 if (uap->info != NULL && error == 0)
776 error = copyout(&si, uap->info, sizeof(si));
781 * Reap the remains of a zombie process and optionally return status and
782 * rusage. Asserts and will release both the proctree_lock and the process
783 * lock as part of its work.
786 proc_reap(struct thread *td, struct proc *p, int *status, int options)
790 sx_assert(&proctree_lock, SA_XLOCKED);
791 PROC_LOCK_ASSERT(p, MA_OWNED);
792 PROC_SLOCK_ASSERT(p, MA_OWNED);
793 KASSERT(p->p_state == PRS_ZOMBIE, ("proc_reap: !PRS_ZOMBIE"));
798 td->td_retval[0] = p->p_pid;
800 *status = p->p_xstat; /* convert to int */
801 if (options & WNOWAIT) {
803 * Only poll, returning the status. Caller does not wish to
804 * release the proc struct just yet.
807 sx_xunlock(&proctree_lock);
812 sigqueue_take(p->p_ksi);
817 * If we got the child via a ptrace 'attach', we need to give it back
820 if (p->p_oppid != 0) {
821 t = proc_realparent(p);
827 pksignal(t, SIGCHLD, p->p_ksi);
829 cv_broadcast(&p->p_pwait);
831 sx_xunlock(&proctree_lock);
836 * Remove other references to this process to ensure we have an
837 * exclusive reference.
839 sx_xlock(&allproc_lock);
840 LIST_REMOVE(p, p_list); /* off zombproc */
841 sx_xunlock(&allproc_lock);
842 LIST_REMOVE(p, p_sibling);
848 if (p->p_procdesc != NULL)
851 sx_xunlock(&proctree_lock);
854 * As a side effect of this lock, we know that all other writes to
855 * this proc are visible now, so no more locking is needed for p.
858 p->p_xstat = 0; /* XXX: why? */
861 ruadd(&q->p_stats->p_cru, &q->p_crux, &p->p_ru, &p->p_rux);
865 * Decrement the count of procs running with this uid.
867 (void)chgproccnt(p->p_ucred->cr_ruidinfo, -1, 0);
870 * Destroy resource accounting information associated with the process.
874 racct_sub(p, RACCT_NPROC, 1);
880 * Free credentials, arguments, and sigacts.
884 pargs_drop(p->p_args);
886 sigacts_free(p->p_sigacts);
890 * Do any thread-system specific cleanups.
895 * Give vm and machine-dependent layer a chance to free anything that
896 * cpu_exit couldn't release while still running in process context.
902 KASSERT(FIRST_THREAD_IN_PROC(p),
903 ("proc_reap: no residual thread!"));
904 uma_zfree(proc_zone, p);
905 sx_xlock(&allproc_lock);
907 sx_xunlock(&allproc_lock);
911 proc_to_reap(struct thread *td, struct proc *p, idtype_t idtype, id_t id,
912 int *status, int options, struct __wrusage *wrusage, siginfo_t *siginfo)
917 sx_assert(&proctree_lock, SA_XLOCKED);
926 if (p->p_pid != (pid_t)id) {
932 if (p->p_pgid != (pid_t)id) {
938 if (p->p_session->s_sid != (pid_t)id) {
944 if (p->p_ucred->cr_uid != (uid_t)id) {
950 if (p->p_ucred->cr_gid != (gid_t)id) {
956 if (p->p_ucred->cr_prison->pr_id != (int)id) {
962 * It seems that the thread structures get zeroed out
963 * at process exit. This makes it impossible to
964 * support P_SETID, P_CID or P_CPUID.
971 if (p_canwait(td, p)) {
976 if (((options & WEXITED) == 0) && (p->p_state == PRS_ZOMBIE)) {
982 * This special case handles a kthread spawned by linux_clone
983 * (see linux_misc.c). The linux_wait4 and linux_waitpid
984 * functions need to be able to distinguish between waiting
985 * on a process and waiting on a thread. It is a thread if
986 * p_sigparent is not SIGCHLD, and the WLINUXCLONE option
987 * signifies we want to wait for threads and not processes.
989 if ((p->p_sigparent != SIGCHLD) ^
990 ((options & WLINUXCLONE) != 0)) {
997 if (siginfo != NULL) {
998 bzero(siginfo, sizeof(*siginfo));
999 siginfo->si_errno = 0;
1002 * SUSv4 requires that the si_signo value is always
1003 * SIGCHLD. Obey it despite the rfork(2) interface
1004 * allows to request other signal for child exit
1007 siginfo->si_signo = SIGCHLD;
1010 * This is still a rough estimate. We will fix the
1011 * cases TRAPPED, STOPPED, and CONTINUED later.
1013 if (WCOREDUMP(p->p_xstat)) {
1014 siginfo->si_code = CLD_DUMPED;
1015 siginfo->si_status = WTERMSIG(p->p_xstat);
1016 } else if (WIFSIGNALED(p->p_xstat)) {
1017 siginfo->si_code = CLD_KILLED;
1018 siginfo->si_status = WTERMSIG(p->p_xstat);
1020 siginfo->si_code = CLD_EXITED;
1021 siginfo->si_status = WEXITSTATUS(p->p_xstat);
1024 siginfo->si_pid = p->p_pid;
1025 siginfo->si_uid = p->p_ucred->cr_uid;
1028 * The si_addr field would be useful additional
1029 * detail, but apparently the PC value may be lost
1030 * when we reach this point. bzero() above sets
1031 * siginfo->si_addr to NULL.
1036 * There should be no reason to limit resources usage info to
1037 * exited processes only. A snapshot about any resources used
1038 * by a stopped process may be exactly what is needed.
1040 if (wrusage != NULL) {
1041 rup = &wrusage->wru_self;
1043 calcru(p, &rup->ru_utime, &rup->ru_stime);
1045 rup = &wrusage->wru_children;
1046 *rup = p->p_stats->p_cru;
1047 calccru(p, &rup->ru_utime, &rup->ru_stime);
1050 if (p->p_state == PRS_ZOMBIE) {
1051 proc_reap(td, p, status, options);
1060 kern_wait(struct thread *td, pid_t pid, int *status, int options,
1061 struct rusage *rusage)
1063 struct __wrusage wru, *wrup;
1069 * Translate the special pid values into the (idtype, pid)
1070 * pair for kern_wait6. The WAIT_MYPGRP case is handled by
1071 * kern_wait6() on its own.
1073 if (pid == WAIT_ANY) {
1076 } else if (pid < 0) {
1090 * For backward compatibility we implicitly add flags WEXITED
1091 * and WTRAPPED here.
1093 options |= WEXITED | WTRAPPED;
1094 ret = kern_wait6(td, idtype, id, status, options, wrup, NULL);
1096 *rusage = wru.wru_self;
1101 kern_wait6(struct thread *td, idtype_t idtype, id_t id, int *status,
1102 int options, struct __wrusage *wrusage, siginfo_t *siginfo)
1105 int error, nfound, ret;
1107 AUDIT_ARG_VALUE((int)idtype); /* XXX - This is likely wrong! */
1108 AUDIT_ARG_PID((pid_t)id); /* XXX - This may be wrong! */
1109 AUDIT_ARG_VALUE(options);
1113 if ((pid_t)id == WAIT_MYPGRP && (idtype == P_PID || idtype == P_PGID)) {
1115 id = (id_t)q->p_pgid;
1120 /* If we don't know the option, just return. */
1121 if ((options & ~(WUNTRACED | WNOHANG | WCONTINUED | WNOWAIT |
1122 WEXITED | WTRAPPED | WLINUXCLONE)) != 0)
1124 if ((options & (WEXITED | WUNTRACED | WCONTINUED | WTRAPPED)) == 0) {
1126 * We will be unable to find any matching processes,
1127 * because there are no known events to look for.
1128 * Prefer to return error instead of blocking
1135 if (q->p_flag & P_STATCHILD) {
1137 q->p_flag &= ~P_STATCHILD;
1141 sx_xlock(&proctree_lock);
1142 LIST_FOREACH(p, &q->p_children, p_sibling) {
1143 ret = proc_to_reap(td, p, idtype, id, status, options,
1155 if ((options & WTRAPPED) != 0 &&
1156 (p->p_flag & P_TRACED) != 0 &&
1157 (p->p_flag & (P_STOPPED_TRACE | P_STOPPED_SIG)) != 0 &&
1158 (p->p_suspcount == p->p_numthreads) &&
1159 ((p->p_flag & P_WAITED) == 0)) {
1161 if ((options & WNOWAIT) == 0)
1162 p->p_flag |= P_WAITED;
1163 sx_xunlock(&proctree_lock);
1164 td->td_retval[0] = p->p_pid;
1167 *status = W_STOPCODE(p->p_xstat);
1168 if (siginfo != NULL) {
1169 siginfo->si_status = p->p_xstat;
1170 siginfo->si_code = CLD_TRAPPED;
1172 if ((options & WNOWAIT) == 0) {
1174 sigqueue_take(p->p_ksi);
1181 if ((options & WUNTRACED) != 0 &&
1182 (p->p_flag & P_STOPPED_SIG) != 0 &&
1183 (p->p_suspcount == p->p_numthreads) &&
1184 ((p->p_flag & P_WAITED) == 0)) {
1186 if ((options & WNOWAIT) == 0)
1187 p->p_flag |= P_WAITED;
1188 sx_xunlock(&proctree_lock);
1189 td->td_retval[0] = p->p_pid;
1192 *status = W_STOPCODE(p->p_xstat);
1193 if (siginfo != NULL) {
1194 siginfo->si_status = p->p_xstat;
1195 siginfo->si_code = CLD_STOPPED;
1197 if ((options & WNOWAIT) == 0) {
1199 sigqueue_take(p->p_ksi);
1207 if ((options & WCONTINUED) != 0 &&
1208 (p->p_flag & P_CONTINUED) != 0) {
1209 sx_xunlock(&proctree_lock);
1210 td->td_retval[0] = p->p_pid;
1211 if ((options & WNOWAIT) == 0) {
1212 p->p_flag &= ~P_CONTINUED;
1214 sigqueue_take(p->p_ksi);
1221 if (siginfo != NULL) {
1222 siginfo->si_status = SIGCONT;
1223 siginfo->si_code = CLD_CONTINUED;
1231 * Look in the orphans list too, to allow the parent to
1232 * collect it's child exit status even if child is being
1235 * Debugger detaches from the parent upon successful
1236 * switch-over from parent to child. At this point due to
1237 * re-parenting the parent loses the child to debugger and a
1238 * wait4(2) call would report that it has no children to wait
1239 * for. By maintaining a list of orphans we allow the parent
1240 * to successfully wait until the child becomes a zombie.
1242 LIST_FOREACH(p, &q->p_orphans, p_orphan) {
1243 ret = proc_to_reap(td, p, idtype, id, status, options,
1253 sx_xunlock(&proctree_lock);
1256 if (options & WNOHANG) {
1257 sx_xunlock(&proctree_lock);
1258 td->td_retval[0] = 0;
1262 sx_xunlock(&proctree_lock);
1263 if (q->p_flag & P_STATCHILD) {
1264 q->p_flag &= ~P_STATCHILD;
1267 error = msleep(q, &q->p_mtx, PWAIT | PCATCH, "wait", 0);
1275 * Make process 'parent' the new parent of process 'child'.
1276 * Must be called with an exclusive hold of proctree lock.
1279 proc_reparent(struct proc *child, struct proc *parent)
1282 sx_assert(&proctree_lock, SX_XLOCKED);
1283 PROC_LOCK_ASSERT(child, MA_OWNED);
1284 if (child->p_pptr == parent)
1287 PROC_LOCK(child->p_pptr);
1288 sigqueue_take(child->p_ksi);
1289 PROC_UNLOCK(child->p_pptr);
1290 LIST_REMOVE(child, p_sibling);
1291 LIST_INSERT_HEAD(&parent->p_children, child, p_sibling);
1293 clear_orphan(child);
1294 if (child->p_flag & P_TRACED) {
1295 if (LIST_EMPTY(&child->p_pptr->p_orphans)) {
1296 child->p_treeflag |= P_TREE_FIRST_ORPHAN;
1297 LIST_INSERT_HEAD(&child->p_pptr->p_orphans, child,
1300 LIST_INSERT_AFTER(LIST_FIRST(&child->p_pptr->p_orphans),
1303 child->p_treeflag |= P_TREE_ORPHANED;
1306 child->p_pptr = parent;