xref: /freebsd/lib/libc/tests/sys/cpuset_test.c (revision 8eb2bee6c0f4957c6c1cea826e59cda4d18a2a64)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2020-2021 Kyle Evans <kevans@FreeBSD.org>
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD");
30 
31 #include <sys/param.h>
32 #include <sys/cpuset.h>
33 #include <sys/jail.h>
34 #include <sys/procdesc.h>
35 #include <sys/select.h>
36 #include <sys/socket.h>
37 #include <sys/uio.h>
38 #include <sys/wait.h>
39 
40 #include <errno.h>
41 #include <stdio.h>
42 #include <unistd.h>
43 
44 #include <atf-c.h>
45 
46 #define	SP_PARENT	0
47 #define	SP_CHILD	1
48 
49 struct jail_test_info {
50 	cpuset_t	jail_tidmask;
51 	cpusetid_t	jail_cpuset;
52 	cpusetid_t	jail_child_cpuset;
53 };
54 
55 struct jail_test_cb_params {
56 	struct jail_test_info		info;
57 	cpuset_t			mask;
58 	cpusetid_t			rootid;
59 	cpusetid_t			setid;
60 };
61 
62 typedef void (*jail_test_cb)(struct jail_test_cb_params *);
63 
64 #define	FAILURE_JAIL	42
65 #define	FAILURE_MASK	43
66 #define	FAILURE_JAILSET	44
67 #define	FAILURE_PIDSET	45
68 #define	FAILURE_SEND	46
69 #define	FAILURE_DEADLK	47
70 #define	FAILURE_ATTACH	48
71 #define	FAILURE_BADAFFIN	49
72 #define	FAILURE_SUCCESS	50
73 
74 static const char *
75 do_jail_errstr(int error)
76 {
77 
78 	switch (error) {
79 	case FAILURE_JAIL:
80 		return ("jail_set(2) failed");
81 	case FAILURE_MASK:
82 		return ("Failed to get the thread cpuset mask");
83 	case FAILURE_JAILSET:
84 		return ("Failed to get the jail setid");
85 	case FAILURE_PIDSET:
86 		return ("Failed to get the pid setid");
87 	case FAILURE_SEND:
88 		return ("Failed to send(2) cpuset information");
89 	case FAILURE_DEADLK:
90 		return ("Deadlock hit trying to attach to jail");
91 	case FAILURE_ATTACH:
92 		return ("jail_attach(2) failed");
93 	case FAILURE_BADAFFIN:
94 		return ("Unexpected post-attach affinity");
95 	case FAILURE_SUCCESS:
96 		return ("jail_attach(2) succeeded, but should have failed.");
97 	default:
98 		return (NULL);
99 	}
100 }
101 
102 static void
103 skip_ltncpu(int ncpu, cpuset_t *mask)
104 {
105 
106 	CPU_ZERO(mask);
107 	ATF_REQUIRE_EQ(0, cpuset_getaffinity(CPU_LEVEL_CPUSET, CPU_WHICH_PID,
108 	    -1, sizeof(*mask), mask));
109 	if (CPU_COUNT(mask) < ncpu)
110 		atf_tc_skip("Test requires %d or more cores.", ncpu);
111 }
112 
113 ATF_TC(newset);
114 ATF_TC_HEAD(newset, tc)
115 {
116 	atf_tc_set_md_var(tc, "descr", "Test cpuset(2)");
117 }
118 ATF_TC_BODY(newset, tc)
119 {
120 	cpusetid_t nsetid, setid, qsetid;
121 
122 	/* Obtain our initial set id. */
123 	ATF_REQUIRE_EQ(0, cpuset_getid(CPU_LEVEL_CPUSET, CPU_WHICH_TID, -1,
124 	    &setid));
125 
126 	/* Create a new one. */
127 	ATF_REQUIRE_EQ(0, cpuset(&nsetid));
128 	ATF_CHECK(nsetid != setid);
129 
130 	/* Query id again, make sure it's equal to the one we just got. */
131 	ATF_REQUIRE_EQ(0, cpuset_getid(CPU_LEVEL_CPUSET, CPU_WHICH_TID, -1,
132 	    &qsetid));
133 	ATF_CHECK_EQ(nsetid, qsetid);
134 }
135 
136 ATF_TC(transient);
137 ATF_TC_HEAD(transient, tc)
138 {
139 	atf_tc_set_md_var(tc, "descr",
140 	   "Test that transient cpusets are freed.");
141 }
142 ATF_TC_BODY(transient, tc)
143 {
144 	cpusetid_t isetid, scratch, setid;
145 
146 	ATF_REQUIRE_EQ(0, cpuset_getid(CPU_LEVEL_CPUSET, CPU_WHICH_PID, -1,
147 	    &isetid));
148 
149 	ATF_REQUIRE_EQ(0, cpuset(&setid));
150 	ATF_REQUIRE_EQ(0, cpuset_getid(CPU_LEVEL_CPUSET, CPU_WHICH_CPUSET,
151 	    setid, &scratch));
152 
153 	/*
154 	 * Return back to our initial cpuset; the kernel should free the cpuset
155 	 * we just created.
156 	 */
157 	ATF_REQUIRE_EQ(0, cpuset_setid(CPU_WHICH_PID, -1, isetid));
158 	ATF_REQUIRE_EQ(-1, cpuset_getid(CPU_LEVEL_CPUSET, CPU_WHICH_CPUSET,
159 	    setid, &scratch));
160 	ATF_CHECK_EQ(ESRCH, errno);
161 }
162 
163 ATF_TC(deadlk);
164 ATF_TC_HEAD(deadlk, tc)
165 {
166 	atf_tc_set_md_var(tc, "descr", "Test against disjoint cpusets.");
167 	atf_tc_set_md_var(tc, "require.user", "root");
168 }
169 ATF_TC_BODY(deadlk, tc)
170 {
171 	cpusetid_t setid;
172 	cpuset_t dismask, mask, omask;
173 	int fcpu, i, found, ncpu, second;
174 
175 	/* Make sure we have 3 cpus, so we test partial overlap. */
176 	skip_ltncpu(3, &omask);
177 
178 	ATF_REQUIRE_EQ(0, cpuset(&setid));
179 	CPU_ZERO(&mask);
180 	CPU_ZERO(&dismask);
181 	CPU_COPY(&omask, &mask);
182 	CPU_COPY(&omask, &dismask);
183 	fcpu = CPU_FFS(&mask);
184 	ncpu = CPU_COUNT(&mask);
185 
186 	/*
187 	 * Turn off all but the first two for mask, turn off the first for
188 	 * dismask and turn them all off for both after the third.
189 	 */
190 	for (i = fcpu - 1, found = 0; i < CPU_MAXSIZE && found != ncpu; i++) {
191 		if (CPU_ISSET(i, &omask)) {
192 			found++;
193 			if (found == 1) {
194 				CPU_CLR(i, &dismask);
195 			} else if (found == 2) {
196 				second = i;
197 			} else if (found >= 3) {
198 				CPU_CLR(i, &mask);
199 				if (found > 3)
200 					CPU_CLR(i, &dismask);
201 			}
202 		}
203 	}
204 
205 	ATF_REQUIRE_EQ(0, cpuset_setaffinity(CPU_LEVEL_CPUSET, CPU_WHICH_PID,
206 	    -1, sizeof(mask), &mask));
207 
208 	/* Must be a strict subset! */
209 	ATF_REQUIRE_EQ(-1, cpuset_setaffinity(CPU_LEVEL_WHICH, CPU_WHICH_TID,
210 	    -1, sizeof(dismask), &dismask));
211 	ATF_REQUIRE_EQ(EINVAL, errno);
212 
213 	/*
214 	 * We'll set our anonymous set to the 0,1 set that currently matches
215 	 * the process.  If we then set the process to the 1,2 set that's in
216 	 * dismask, we should then personally be restricted down to the single
217 	 * overlapping CPOU.
218 	 */
219 	ATF_REQUIRE_EQ(0, cpuset_setaffinity(CPU_LEVEL_WHICH, CPU_WHICH_TID,
220 	    -1, sizeof(mask), &mask));
221 	ATF_REQUIRE_EQ(0, cpuset_setaffinity(CPU_LEVEL_CPUSET, CPU_WHICH_PID,
222 	    -1, sizeof(dismask), &dismask));
223 	ATF_REQUIRE_EQ(0, cpuset_getaffinity(CPU_LEVEL_WHICH, CPU_WHICH_TID,
224 	    -1, sizeof(mask), &mask));
225 	ATF_REQUIRE_EQ(1, CPU_COUNT(&mask));
226 	ATF_REQUIRE(CPU_ISSET(second, &mask));
227 
228 	/*
229 	 * Finally, clearing the overlap and attempting to set the process
230 	 * cpuset to a completely disjoint mask should fail, because this
231 	 * process will then not have anything to run on.
232 	 */
233 	CPU_CLR(second, &dismask);
234 	ATF_REQUIRE_EQ(-1, cpuset_setaffinity(CPU_LEVEL_CPUSET, CPU_WHICH_PID,
235 	    -1, sizeof(dismask), &dismask));
236 	ATF_REQUIRE_EQ(EDEADLK, errno);
237 }
238 
239 static int
240 do_jail(int sock)
241 {
242 	struct jail_test_info info;
243 	struct iovec iov[2];
244 	char *name;
245 	int error;
246 
247 	if (asprintf(&name, "cpuset_%d", getpid()) == -1)
248 		_exit(42);
249 
250 	iov[0].iov_base = "name";
251 	iov[0].iov_len = 5;
252 
253 	iov[1].iov_base = name;
254 	iov[1].iov_len = strlen(name) + 1;
255 
256 	if (jail_set(iov, 2, JAIL_CREATE | JAIL_ATTACH) < 0)
257 		return (FAILURE_JAIL);
258 
259 	/* Record parameters, kick them over, then make a swift exit. */
260 	CPU_ZERO(&info.jail_tidmask);
261 	error = cpuset_getaffinity(CPU_LEVEL_WHICH, CPU_WHICH_TID,
262 	    -1, sizeof(info.jail_tidmask), &info.jail_tidmask);
263 	if (error != 0)
264 		return (FAILURE_MASK);
265 
266 	error = cpuset_getid(CPU_LEVEL_ROOT, CPU_WHICH_TID, -1,
267 	    &info.jail_cpuset);
268 	if (error != 0)
269 		return (FAILURE_JAILSET);
270 	error = cpuset_getid(CPU_LEVEL_CPUSET, CPU_WHICH_TID, -1,
271 	    &info.jail_child_cpuset);
272 	if (error != 0)
273 		return (FAILURE_PIDSET);
274 	if (send(sock, &info, sizeof(info), 0) != sizeof(info))
275 		return (FAILURE_SEND);
276 	return (0);
277 }
278 
279 static void
280 do_jail_test(int ncpu, bool newset, jail_test_cb prologue,
281     jail_test_cb epilogue)
282 {
283 	struct jail_test_cb_params cbp;
284 	const char *errstr;
285 	pid_t pid;
286 	int error, sock, sockpair[2], status;
287 
288 	memset(&cbp.info, '\0', sizeof(cbp.info));
289 
290 	skip_ltncpu(ncpu, &cbp.mask);
291 
292 	ATF_REQUIRE_EQ(0, cpuset_getid(CPU_LEVEL_ROOT, CPU_WHICH_PID, -1,
293 	    &cbp.rootid));
294 	if (newset)
295 		ATF_REQUIRE_EQ(0, cpuset(&cbp.setid));
296 	else
297 		ATF_REQUIRE_EQ(0, cpuset_getid(CPU_LEVEL_CPUSET, CPU_WHICH_PID,
298 		    -1, &cbp.setid));
299 	/* Special hack for prison0; it uses cpuset 1 as the root. */
300 	if (cbp.rootid == 0)
301 		cbp.rootid = 1;
302 
303 	/* Not every test needs early setup. */
304 	if (prologue != NULL)
305 		(*prologue)(&cbp);
306 
307 	ATF_REQUIRE_EQ(0, socketpair(PF_UNIX, SOCK_STREAM, 0, sockpair));
308 	ATF_REQUIRE((pid = fork()) != -1);
309 
310 	if (pid == 0) {
311 		/* Child */
312 		close(sockpair[SP_PARENT]);
313 		sock = sockpair[SP_CHILD];
314 
315 		_exit(do_jail(sock));
316 	} else {
317 		/* Parent */
318 		sock = sockpair[SP_PARENT];
319 		close(sockpair[SP_CHILD]);
320 
321 		while ((error = waitpid(pid, &status, 0)) == -1 &&
322 		    errno == EINTR) {
323 		}
324 
325 		ATF_REQUIRE_EQ(sizeof(cbp.info), recv(sock, &cbp.info,
326 		    sizeof(cbp.info), 0));
327 
328 		/* Sanity check the exit info. */
329 		ATF_REQUIRE_EQ(pid, error);
330 		ATF_REQUIRE(WIFEXITED(status));
331 		if (WEXITSTATUS(status) != 0) {
332 			errstr = do_jail_errstr(WEXITSTATUS(status));
333 			if (errstr != NULL)
334 				atf_tc_fail("%s", errstr);
335 			else
336 				atf_tc_fail("Unknown error '%d'",
337 				    WEXITSTATUS(status));
338 		}
339 
340 		epilogue(&cbp);
341 	}
342 }
343 
344 static void
345 jail_attach_mutate_pro(struct jail_test_cb_params *cbp)
346 {
347 	cpuset_t *mask;
348 	int count;
349 
350 	mask = &cbp->mask;
351 
352 	/* Knock out the first cpu. */
353 	count = CPU_COUNT(mask);
354 	CPU_CLR(CPU_FFS(mask) - 1, mask);
355 	ATF_REQUIRE_EQ(count - 1, CPU_COUNT(mask));
356 	ATF_REQUIRE_EQ(0, cpuset_setaffinity(CPU_LEVEL_WHICH, CPU_WHICH_TID,
357 	    -1, sizeof(*mask), mask));
358 }
359 
360 static void
361 jail_attach_newbase_epi(struct jail_test_cb_params *cbp)
362 {
363 	struct jail_test_info *info;
364 	cpuset_t *mask;
365 
366 	info = &cbp->info;
367 	mask = &cbp->mask;
368 
369 	/*
370 	 * The rootid test has been thrown in because a bug was discovered
371 	 * where any newly derived cpuset during attach would be parented to
372 	 * the wrong cpuset.  Otherwise, we should observe that a new cpuset
373 	 * has been created for this process.
374 	 */
375 	ATF_REQUIRE(info->jail_cpuset != cbp->rootid);
376 	ATF_REQUIRE(info->jail_cpuset != cbp->setid);
377 	ATF_REQUIRE(info->jail_cpuset != info->jail_child_cpuset);
378 	ATF_REQUIRE_EQ(0, CPU_CMP(mask, &info->jail_tidmask));
379 }
380 
381 ATF_TC(jail_attach_newbase);
382 ATF_TC_HEAD(jail_attach_newbase, tc)
383 {
384 	atf_tc_set_md_var(tc, "descr",
385 	    "Test jail attachment effect on affinity with a new base cpuset.");
386 	atf_tc_set_md_var(tc, "require.user", "root");
387 }
388 ATF_TC_BODY(jail_attach_newbase, tc)
389 {
390 
391 	/* Need >= 2 cpus to test restriction. */
392 	do_jail_test(2, true, &jail_attach_mutate_pro,
393 	    &jail_attach_newbase_epi);
394 }
395 
396 ATF_TC(jail_attach_newbase_plain);
397 ATF_TC_HEAD(jail_attach_newbase_plain, tc)
398 {
399 	atf_tc_set_md_var(tc, "descr",
400 	    "Test jail attachment effect on affinity with a new, unmodified base cpuset.");
401 	atf_tc_set_md_var(tc, "require.user", "root");
402 }
403 ATF_TC_BODY(jail_attach_newbase_plain, tc)
404 {
405 
406 	do_jail_test(2, true, NULL, &jail_attach_newbase_epi);
407 }
408 
409 /*
410  * Generic epilogue for tests that are expecting to use the jail's root cpuset
411  * with their own mask, whether that's been modified or not.
412  */
413 static void
414 jail_attach_jset_epi(struct jail_test_cb_params *cbp)
415 {
416 	struct jail_test_info *info;
417 	cpuset_t *mask;
418 
419 	info = &cbp->info;
420 	mask = &cbp->mask;
421 
422 	ATF_REQUIRE(info->jail_cpuset != cbp->setid);
423 	ATF_REQUIRE_EQ(info->jail_cpuset, info->jail_child_cpuset);
424 	ATF_REQUIRE_EQ(0, CPU_CMP(mask, &info->jail_tidmask));
425 }
426 
427 ATF_TC(jail_attach_prevbase);
428 ATF_TC_HEAD(jail_attach_prevbase, tc)
429 {
430 	atf_tc_set_md_var(tc, "descr",
431 	    "Test jail attachment effect on affinity without a new base.");
432 	atf_tc_set_md_var(tc, "require.user", "root");
433 }
434 ATF_TC_BODY(jail_attach_prevbase, tc)
435 {
436 
437 	do_jail_test(2, false, &jail_attach_mutate_pro, &jail_attach_jset_epi);
438 }
439 
440 static void
441 jail_attach_plain_pro(struct jail_test_cb_params *cbp)
442 {
443 
444 	if (cbp->setid != cbp->rootid)
445 		atf_tc_skip("Must be running with the root cpuset.");
446 }
447 
448 ATF_TC(jail_attach_plain);
449 ATF_TC_HEAD(jail_attach_plain, tc)
450 {
451 	atf_tc_set_md_var(tc, "descr",
452 	    "Test jail attachment effect on affinity without specialization.");
453 	atf_tc_set_md_var(tc, "require.user", "root");
454 }
455 ATF_TC_BODY(jail_attach_plain, tc)
456 {
457 
458 	do_jail_test(1, false, &jail_attach_plain_pro, &jail_attach_jset_epi);
459 }
460 
461 static int
462 jail_attach_disjoint_newjail(int fd)
463 {
464 	struct iovec iov[2];
465 	char *name;
466 	int jid;
467 
468 	if (asprintf(&name, "cpuset_%d", getpid()) == -1)
469 		_exit(42);
470 
471 	iov[0].iov_base = "name";
472 	iov[0].iov_len = sizeof("name");
473 
474 	iov[1].iov_base = name;
475 	iov[1].iov_len = strlen(name) + 1;
476 
477 	if ((jid = jail_set(iov, 2, JAIL_CREATE | JAIL_ATTACH)) < 0)
478 		return (FAILURE_JAIL);
479 
480 	/* Signal that we're ready. */
481 	write(fd, &jid, sizeof(jid));
482 	for (;;) {
483 		/* Spin */
484 	}
485 }
486 
487 static int
488 wait_jail(int fd, int pfd)
489 {
490 	fd_set lset;
491 	struct timeval tv;
492 	int error, jid, maxfd;
493 
494 	FD_ZERO(&lset);
495 	FD_SET(fd, &lset);
496 	FD_SET(pfd, &lset);
497 
498 	maxfd = MAX(fd, pfd);
499 
500 	tv.tv_sec = 5;
501 	tv.tv_usec = 0;
502 
503 	/* Wait for jid to be written. */
504 	do {
505 		error = select(maxfd + 1, &lset, NULL, NULL, &tv);
506 	} while (error == -1 && errno == EINTR);
507 
508 	if (error == 0) {
509 		atf_tc_fail("Jail creator did not respond in time.");
510 	}
511 
512 	ATF_REQUIRE_MSG(error > 0, "Unexpected error %d from select()", errno);
513 
514 	if (FD_ISSET(pfd, &lset)) {
515 		/* Process died */
516 		atf_tc_fail("Jail creator died unexpectedly.");
517 	}
518 
519 	ATF_REQUIRE(FD_ISSET(fd, &lset));
520 	ATF_REQUIRE_EQ(sizeof(jid), recv(fd, &jid, sizeof(jid), 0));
521 
522 	return (jid);
523 }
524 
525 static int
526 try_attach_child(int jid, cpuset_t *expected_mask)
527 {
528 	cpuset_t mask;
529 
530 	if (jail_attach(jid) == -1) {
531 		if (errno == EDEADLK)
532 			return (FAILURE_DEADLK);
533 		return (FAILURE_ATTACH);
534 	}
535 
536 	if (expected_mask == NULL)
537 		return (FAILURE_SUCCESS);
538 
539 	/* If we had an expected mask, check it against the new process mask. */
540 	CPU_ZERO(&mask);
541 	if (cpuset_getaffinity(CPU_LEVEL_CPUSET, CPU_WHICH_PID,
542 	    -1, sizeof(mask), &mask) != 0) {
543 		return (FAILURE_MASK);
544 	}
545 
546 	if (CPU_CMP(expected_mask, &mask) != 0)
547 		return (FAILURE_BADAFFIN);
548 
549 	return (0);
550 }
551 
552 static void
553 try_attach(int jid, cpuset_t *expected_mask)
554 {
555 	const char *errstr;
556 	pid_t pid;
557 	int error, fail, status;
558 
559 	ATF_REQUIRE(expected_mask != NULL);
560 	ATF_REQUIRE((pid = fork()) != -1);
561 	if (pid == 0)
562 		_exit(try_attach_child(jid, expected_mask));
563 
564 	while ((error = waitpid(pid, &status, 0)) == -1 && errno == EINTR) {
565 		/* Try again. */
566 	}
567 
568 	/* Sanity check the exit info. */
569 	ATF_REQUIRE_EQ(pid, error);
570 	ATF_REQUIRE(WIFEXITED(status));
571 	if ((fail = WEXITSTATUS(status)) != 0) {
572 		errstr = do_jail_errstr(fail);
573 		if (errstr != NULL)
574 			atf_tc_fail("%s", errstr);
575 		else
576 			atf_tc_fail("Unknown error '%d'", WEXITSTATUS(status));
577 	}
578 }
579 
580 ATF_TC(jail_attach_disjoint);
581 ATF_TC_HEAD(jail_attach_disjoint, tc)
582 {
583 	atf_tc_set_md_var(tc, "descr",
584 	    "Test root attachment into completely disjoint jail cpuset.");
585 	atf_tc_set_md_var(tc, "require.user", "root");
586 }
587 ATF_TC_BODY(jail_attach_disjoint, tc)
588 {
589 	cpuset_t smask, jmask;
590 	int sockpair[2];
591 	cpusetid_t setid;
592 	pid_t pid;
593 	int fcpu, jid, pfd, sock, scpu;
594 
595 	ATF_REQUIRE_EQ(0, cpuset(&setid));
596 
597 	skip_ltncpu(2, &jmask);
598 	fcpu = CPU_FFS(&jmask) - 1;
599 	ATF_REQUIRE_EQ(0, socketpair(PF_UNIX, SOCK_STREAM, 0, sockpair));
600 
601 	/* We'll wait on the procdesc, too, so we can fail faster if it dies. */
602 	ATF_REQUIRE((pid = pdfork(&pfd, 0)) != -1);
603 
604 	if (pid == 0) {
605 		/* First child sets up the jail. */
606 		sock = sockpair[SP_CHILD];
607 		close(sockpair[SP_PARENT]);
608 
609 		_exit(jail_attach_disjoint_newjail(sock));
610 	}
611 
612 	close(sockpair[SP_CHILD]);
613 	sock = sockpair[SP_PARENT];
614 
615 	ATF_REQUIRE((jid = wait_jail(sock, pfd)) > 0);
616 
617 	/*
618 	 * This process will be clamped down to the first cpu, while the jail
619 	 * will simply have the first CPU removed to make it a completely
620 	 * disjoint operation.
621 	 */
622 	CPU_ZERO(&smask);
623 	CPU_SET(fcpu, &smask);
624 	CPU_CLR(fcpu, &jmask);
625 
626 	/*
627 	 * We'll test with the first and second cpu set as well.  Only the
628 	 * second cpu should be used.
629 	 */
630 	scpu = CPU_FFS(&jmask) - 1;
631 
632 	ATF_REQUIRE_EQ(0, cpuset_setaffinity(CPU_LEVEL_ROOT, CPU_WHICH_JAIL,
633 	    jid, sizeof(jmask), &jmask));
634 	ATF_REQUIRE_EQ(0, cpuset_setaffinity(CPU_LEVEL_CPUSET, CPU_WHICH_CPUSET,
635 	    setid, sizeof(smask), &smask));
636 
637 	try_attach(jid, &jmask);
638 
639 	CPU_SET(scpu, &smask);
640 	ATF_REQUIRE_EQ(0, cpuset_setaffinity(CPU_LEVEL_CPUSET, CPU_WHICH_CPUSET,
641 	    setid, sizeof(smask), &smask));
642 
643 	CPU_CLR(fcpu, &smask);
644 	try_attach(jid, &smask);
645 }
646 
647 ATF_TC(badparent);
648 ATF_TC_HEAD(badparent, tc)
649 {
650 	atf_tc_set_md_var(tc, "descr",
651 	    "Test parent assignment when assigning a new cpuset.");
652 }
653 ATF_TC_BODY(badparent, tc)
654 {
655 	cpuset_t mask;
656 	cpusetid_t finalsetid, origsetid, setid;
657 
658 	/* Need to mask off at least one CPU. */
659 	skip_ltncpu(2, &mask);
660 
661 	ATF_REQUIRE_EQ(0, cpuset_getid(CPU_LEVEL_CPUSET, CPU_WHICH_TID, -1,
662 	    &origsetid));
663 
664 	ATF_REQUIRE_EQ(0, cpuset(&setid));
665 
666 	/*
667 	 * Mask off the first CPU, then we'll reparent ourselves to our original
668 	 * set.
669 	 */
670 	CPU_CLR(CPU_FFS(&mask) - 1, &mask);
671 	ATF_REQUIRE_EQ(0, cpuset_setaffinity(CPU_LEVEL_WHICH, CPU_WHICH_TID,
672 	    -1, sizeof(mask), &mask));
673 
674 	ATF_REQUIRE_EQ(0, cpuset_setid(CPU_WHICH_PID, -1, origsetid));
675 	ATF_REQUIRE_EQ(0, cpuset_getid(CPU_LEVEL_CPUSET, CPU_WHICH_TID, -1,
676 	    &finalsetid));
677 
678 	ATF_REQUIRE_EQ(finalsetid, origsetid);
679 }
680 
681 ATF_TP_ADD_TCS(tp)
682 {
683 
684 	ATF_TP_ADD_TC(tp, newset);
685 	ATF_TP_ADD_TC(tp, transient);
686 	ATF_TP_ADD_TC(tp, deadlk);
687 	ATF_TP_ADD_TC(tp, jail_attach_newbase);
688 	ATF_TP_ADD_TC(tp, jail_attach_newbase_plain);
689 	ATF_TP_ADD_TC(tp, jail_attach_prevbase);
690 	ATF_TP_ADD_TC(tp, jail_attach_plain);
691 	ATF_TP_ADD_TC(tp, jail_attach_disjoint);
692 	ATF_TP_ADD_TC(tp, badparent);
693 	return (atf_no_error());
694 }
695