1 /*
2 * This file and its contents are supplied under the terms of the
3 * Common Development and Distribution License ("CDDL"), version 1.0.
4 * You may only use this file in accordance with the terms of version
5 * 1.0 of the CDDL.
6 *
7 * A full copy of the text of the CDDL should have accompanied this
8 * source. A copy of the CDDL is also available via the Internet at
9 * http://www.illumos.org/license/CDDL.
10 */
11
12 /*
13 * Copyright 2018 Joyent, Inc.
14 */
15
16 #include <sys/types.h>
17 #include <sys/sysi86.h>
18 #include <sys/segments.h>
19 #include <sys/segment.h>
20 #include <unistd.h>
21 #include <string.h>
22 #include <errno.h>
23 #include <pthread.h>
24 #include <err.h>
25
26 char foo[4096];
27
28 static void *
donothing(void * nothing)29 donothing(void *nothing)
30 {
31 (void) sleep(5);
32 return (NULL);
33 }
34
35 int
main(void)36 main(void)
37 {
38 pthread_t tid;
39
40 /*
41 * This first is similar to what sbcl does in some variants. Note the
42 * SDT_MEMRW (not SDT_MEMRWA) so we check that the kernel is forcing the
43 * 'accessed' bit too.
44 */
45 int sel = SEL_LDT(7);
46
47 struct ssd ssd = { sel, (unsigned long)&foo, 4096,
48 SDT_MEMRW | (SEL_UPL << 5) | (1 << 7), 0x4 };
49
50 if (sysi86(SI86DSCR, &ssd) < 0)
51 err(-1, "failed to setup segment");
52
53 __asm__ __volatile__("mov %0, %%fs" : : "r" (sel));
54
55 ssd.acc1 = 0;
56
57 if (sysi86(SI86DSCR, &ssd) == 0)
58 errx(-1, "removed in-use segment?");
59
60 __asm__ __volatile__("mov %0, %%fs" : : "r" (0));
61
62 if (sysi86(SI86DSCR, &ssd) < 0)
63 err(-1, "failed to remove segment");
64
65 for (int i = 0; i < MAXNLDT; i++) {
66 ssd.sel = SEL_LDT(i);
67 (void) sysi86(SI86DSCR, &ssd);
68 }
69
70 for (int i = 0; i < 10; i++)
71 (void) pthread_create(&tid, NULL, donothing, NULL);
72
73 if (forkall() == 0) {
74 (void) sleep(2);
75 _exit(0);
76 }
77
78 (void) sleep(6);
79 return (0);
80 }
81