1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2021 ARM Limited
4 *
5 * Verify that using an instruction not supported in streaming mode
6 * traps when in streaming mode.
7 */
8
9#include <signal.h>
10#include <ucontext.h>
11#include <sys/prctl.h>
12
13#include "test_signals_utils.h"
14#include "testcases.h"
15
16static union {
17 ucontext_t uc;
18 char buf[1024 * 128];
19} context;
20
21static void enable_za(void)
22{
23 /* smstart za; real data is TODO */
24 asm volatile(".inst 0xd503457f" : : : );
25}
26
27int zt_regs_run(struct tdescr *td, siginfo_t *si, ucontext_t *uc)
28{
29 size_t offset;
30 struct _aarch64_ctx *head = GET_BUF_RESV_HEAD(context);
31 struct zt_context *zt;
32 char *zeros;
33
34 /*
35 * Get a signal context which should have a ZT frame and registers
36 * in it.
37 */
38 enable_za();
39 if (!get_current_context(td, &context.uc, sizeof(context)))
40 return 1;
41
42 head = get_header(head, magic: ZT_MAGIC, GET_BUF_RESV_SIZE(context), offset: &offset);
43 if (!head) {
44 fprintf(stderr, "No ZT context\n");
45 return 1;
46 }
47
48 zt = (struct zt_context *)head;
49 if (zt->nregs == 0) {
50 fprintf(stderr, "Got context with no registers\n");
51 return 1;
52 }
53
54 fprintf(stderr, "Got expected size %u for %d registers\n",
55 head->size, zt->nregs);
56
57 /* We didn't load any data into ZT so it should be all zeros */
58 zeros = malloc(ZT_SIG_REGS_SIZE(zt->nregs));
59 if (!zeros) {
60 fprintf(stderr, "Out of memory, nregs=%u\n", zt->nregs);
61 return 1;
62 }
63 memset(zeros, 0, ZT_SIG_REGS_SIZE(zt->nregs));
64
65 if (memcmp(zeros, (char *)zt + ZT_SIG_REGS_OFFSET,
66 ZT_SIG_REGS_SIZE(zt->nregs)) != 0) {
67 fprintf(stderr, "ZT data invalid\n");
68 free(zeros);
69 return 1;
70 }
71
72 free(zeros);
73
74 td->pass = 1;
75
76 return 0;
77}
78
79struct tdescr tde = {
80 .name = "ZT register data",
81 .descr = "Validate that ZT is present and has data when ZA is enabled",
82 .feats_required = FEAT_SME2,
83 .timeout = 3,
84 .sanity_disabled = true,
85 .run = zt_regs_run,
86};
87

source code of linux/tools/testing/selftests/arm64/signal/testcases/zt_regs.c