1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2022 ARM Limited
4 *
5 * Verify that the TPIDR2 register context in signal frames is set up as
6 * expected.
7 */
8
9 #include <signal.h>
10 #include <ucontext.h>
11 #include <sys/auxv.h>
12 #include <sys/prctl.h>
13 #include <unistd.h>
14 #include <asm/sigcontext.h>
15
16 #include "test_signals_utils.h"
17 #include "testcases.h"
18
19 static union {
20 ucontext_t uc;
21 char buf[1024 * 128];
22 } context;
23
24 #define SYS_TPIDR2 "S3_3_C13_C0_5"
25
get_tpidr2(void)26 static uint64_t get_tpidr2(void)
27 {
28 uint64_t val;
29
30 asm volatile (
31 "mrs %0, " SYS_TPIDR2 "\n"
32 : "=r"(val)
33 :
34 : "cc");
35
36 return val;
37 }
38
tpidr2_present(struct tdescr * td,siginfo_t * si,ucontext_t * uc)39 int tpidr2_present(struct tdescr *td, siginfo_t *si, ucontext_t *uc)
40 {
41 struct _aarch64_ctx *head = GET_BUF_RESV_HEAD(context);
42 struct tpidr2_context *tpidr2_ctx;
43 size_t offset;
44 bool in_sigframe;
45 bool have_sme;
46 __u64 orig_tpidr2;
47
48 have_sme = getauxval(AT_HWCAP2) & HWCAP2_SME;
49 if (have_sme)
50 orig_tpidr2 = get_tpidr2();
51
52 if (!get_current_context(td, &context.uc, sizeof(context)))
53 return 1;
54
55 tpidr2_ctx = (struct tpidr2_context *)
56 get_header(head, TPIDR2_MAGIC, td->live_sz, &offset);
57
58 in_sigframe = tpidr2_ctx != NULL;
59
60 fprintf(stderr, "TPIDR2 sigframe %s on system %s SME\n",
61 in_sigframe ? "present" : "absent",
62 have_sme ? "with" : "without");
63
64 td->pass = (in_sigframe == have_sme);
65
66 /*
67 * Check that the value we read back was the one present at
68 * the time that the signal was triggered. TPIDR2 is owned by
69 * libc so we can't safely choose the value and it is possible
70 * that we may need to revisit this in future if something
71 * starts deciding to set a new TPIDR2 between us reading and
72 * the signal.
73 */
74 if (have_sme && tpidr2_ctx) {
75 if (tpidr2_ctx->tpidr2 != orig_tpidr2) {
76 fprintf(stderr, "TPIDR2 in frame is %llx, was %llx\n",
77 tpidr2_ctx->tpidr2, orig_tpidr2);
78 td->pass = false;
79 }
80 }
81
82 return 0;
83 }
84
85 struct tdescr tde = {
86 .name = "TPIDR2",
87 .descr = "Validate that TPIDR2 is present as expected",
88 .timeout = 3,
89 .run = tpidr2_present,
90 };
91