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 * This test verifies the following:
18 *
19 * o xregs and fpregs report the same content for the xmm registers at least.
20 * o A write to xregs is reflected in reads of fpregs.
21 * o A write to the fpregs is reflected in reads of xregs and doesn't
22 * clobber additional state in xregs.
23 * o A thread in our victim process sees the final state here and can print
24 * that out.
25 * o As a side effect it makes sure that libproc isn't incorrectly caching
26 * register info on handles.
27 *
28 * We use the xsu_dump process of the same bitness as us.
29 */
30
31 #include <err.h>
32 #include <stdlib.h>
33 #include <errno.h>
34 #include <string.h>
35
36 #include "xsave_util.h"
37
38 static xsu_fpu_t fpu;
39
40 int
main(int argc,char * argv[])41 main(int argc, char *argv[])
42 {
43 uint32_t seed, hwsup;
44 unsigned long ul;
45 char *eptr;
46 prxregset_t *prx, *cmp_prx;
47 size_t prx_len, cmp_prx_len;
48 xsu_proc_t xp;
49 fpregset_t fpr;
50
51 if (argc != 5) {
52 errx(EXIT_FAILURE, "missing args: <prog> <output file> "
53 "<seed> <func>");
54 }
55
56 errno = 0;
57 ul = strtoul(argv[3], &eptr, 0);
58 if (errno != 0 || *eptr != '\0') {
59 errx(EXIT_FAILURE, "seed value is bad: %s", argv[3]);
60 }
61
62 #if defined(_LP64)
63 if (ul > UINT32_MAX) {
64 errx(EXIT_FAILURE, "seed %s outside of [0, UINT32_MAX]",
65 argv[3]);
66 }
67 #endif
68
69 seed = (uint32_t)ul;
70 hwsup = xsu_hwsupport();
71 xsu_fill(&fpu, hwsup, seed);
72 xsu_fpu_to_xregs(&fpu, hwsup, &prx, &prx_len);
73
74 (void) memset(&xp, 0, sizeof (xsu_proc_t));
75 xp.xp_prog = argv[1];
76 xp.xp_arg = argv[2];
77 xp.xp_object = "a.out";
78 xp.xp_symname = argv[4];
79 xsu_proc_bkpt(&xp);
80
81 /*
82 * First get the xregs into a reasonable place.
83 */
84 if (Plwp_setxregs(xp.xp_proc, 1, prx, prx_len) != 0) {
85 err(EXIT_FAILURE, "failed to set target's xregs");
86 }
87
88 /*
89 * Now that we have that, let's go and get the fpregs. Because of
90 * differences between the 32-bit representation and the xsave state in
91 * the xregs, we stick to different checking in an ILP32 vs. LP64 pieces
92 * of this.
93 */
94 if (Plwp_getfpregs(xp.xp_proc, 1, &fpr) != 0) {
95 err(EXIT_FAILURE, "failed to get the fp registers");
96 }
97
98 if (!xsu_fpregs_cmp(&fpr, prx)) {
99 errx(EXIT_FAILURE, "fpregs do not reflect xsave changes!");
100 }
101 (void) printf("TEST PASSED: fpregs read respects xregs write\n");
102
103 /*
104 * Override the xmm registers with the known variant of the seed and set
105 * that. Update the xregs data so we can later compare them usefully.
106 */
107 xsu_fpregset_xmm_set(&fpr, seed + INT32_MAX);
108 xsu_xregs_xmm_set(prx, seed + INT32_MAX);
109 if (Plwp_setfpregs(xp.xp_proc, 1, &fpr) != 0) {
110 err(EXIT_FAILURE, "failed to set fpregs");
111 }
112
113 if (Plwp_getxregs(xp.xp_proc, 1, &cmp_prx, &cmp_prx_len) != 0) {
114 err(EXIT_FAILURE, "failed to get comparison xregs");
115 }
116
117 if (!xsu_fpregs_cmp(&fpr, cmp_prx)) {
118 errx(EXIT_FAILURE, "fpregs do not reflect xsave changes!");
119 }
120 (void) printf("TEST PASSED: xregs read respects fpregs write\n");
121
122 if (!xsu_xregs_comp_equal(prx, cmp_prx, PRX_INFO_YMM)) {
123 errx(EXIT_FAILURE, "%%ymm state changed across fpregs write");
124 }
125 (void) printf("TEST PASSED: fpregs did not change other xregs "
126 "components\n");
127
128 xsu_proc_finish(&xp);
129
130 return (EXIT_SUCCESS);
131 }
132