xref: /illumos-gate/usr/src/test/os-tests/tests/xsave/fpregs.c (revision 8119dad84d6416f13557b0ba8e2aaf9064cbcfd3)
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
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