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 2023 Oxide Computer Company
14 */
15
16 /*
17 * Verify that we can read the xregs of a thread and write them back intact.
18 * This uses libproc as a wrapper. We then start the thread running again and
19 * attempt to write to /proc ourselves to expect an EBUSY because the thread is
20 * not stopped.
21 */
22
23 #include <libproc.h>
24 #include <thread.h>
25 #include <stdlib.h>
26 #include <err.h>
27 #include <errno.h>
28 #include <string.h>
29 #include <sys/sysmacros.h>
30
31 #include "xsave_util.h"
32
33 int
main(void)34 main(void)
35 {
36 int ret, fd;
37 ssize_t sret;
38 struct ps_prochandle *P;
39 struct ps_lwphandle *L;
40 thread_t targ;
41 prxregset_t *prx, *prx_alt;
42 size_t prx_len, prx_alt_len;
43 struct iovec iov[2];
44 long cmd = PCSXREG;
45
46 P = Pgrab(getpid(), PGRAB_RDONLY, &ret);
47 if (P == NULL) {
48 errx(EXIT_FAILURE, "failed to grab ourself: %s",
49 Pgrab_error(ret));
50 }
51
52 ret = thr_create(NULL, 0, xsu_sleeper_thread, NULL, THR_DETACHED,
53 &targ);
54 if (ret != 0) {
55 errc(EXIT_FAILURE, ret, "failed to create sleeper thread");
56 }
57
58 L = Lgrab(P, targ, &ret);
59 if (L == NULL) {
60 errx(EXIT_FAILURE, "failed to grab our sleeper thread: %s",
61 Lgrab_error(ret));
62 }
63
64 ret = Lstop(L, 0);
65 if (ret != 0) {
66 err(EXIT_FAILURE, "failed to stop the sleeper thread");
67 }
68
69 if (Lgetxregs(L, &prx, &prx_len) != 0) {
70 err(EXIT_FAILURE, "failed to get xregs");
71 }
72
73 (void) printf("TEST PASSED: successfully got initial xregs\n");
74
75 if (Lsetxregs(L, prx, prx_len) != 0) {
76 err(EXIT_FAILURE, "failed to set xregs");
77 }
78
79 (void) printf("TEST PASSED: successfully set xregs\n");
80
81 if (Lgetxregs(L, &prx_alt, &prx_alt_len) != 0) {
82 err(EXIT_FAILURE, "failed to get xregs after write");
83 }
84
85 if (prx_len != prx_alt_len) {
86 errx(EXIT_FAILURE, "xreg length changed across a write: "
87 "originally found %zu, now %zu", prx_len, prx_alt_len);
88 }
89
90 if (memcmp(prx, prx_alt, prx_len) != 0) {
91 const uint8_t *a = (uint8_t *)prx;
92 const uint8_t *b = (uint8_t *)prx_alt;
93 for (size_t i = 0; i < prx_len; i++) {
94 if (a[i] != b[i]) {
95 (void) fprintf(stderr, "prx[0x%x] = 0x%02x, "
96 "prx_alt[0x%x] = 0x%02x\n", i, a[i], i,
97 b[i]);
98 }
99 }
100 errx(EXIT_FAILURE, "xregs were not the same!");
101 }
102
103 (void) printf("TEST PASSED: round-trip xregs\n");
104
105 if (Lsetrun(L, 0, 0) != 0) {
106 err(EXIT_FAILURE, "failed to start sleeper thread");
107 }
108
109 /*
110 * We write to /proc directly ourselves as a way to avoid libproc's own
111 * checks for the state of the thread.
112 */
113 fd = Lctlfd(L);
114 if (fd < 0) {
115 errx(EXIT_FAILURE, "failed to get sleeper thread control d");
116 }
117
118 iov[0].iov_base = (char *)&cmd;
119 iov[0].iov_len = sizeof (long);
120 iov[1].iov_base = (char *)prx;
121 iov[1].iov_len = prx_len;
122 sret = writev(fd, iov, ARRAY_SIZE(iov));
123 if (sret != -1) {
124 errx(EXIT_FAILURE, "writev returned %zd, but expected -1",
125 sret);
126 }
127
128 if (errno != EBUSY) {
129 errx(EXIT_FAILURE, "xregs error was not EBUSY, got %d!", errno);
130 }
131
132 (void) printf("TEST PASSED: got EBUSY with PCSXREG to running "
133 "thread\n");
134 Plwp_freexregs(P, prx, prx_len);
135 return (EXIT_SUCCESS);
136 }
137