projects/linux·blob master · refs

67 lines · 1.6 KiB

1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright 2016, Chris Smart, IBM Corporation.
4 *
5 * Calls to copy_first which are not 128-byte aligned should be
6 * caught and sent a SIGBUS.
7 */
8
9#include <signal.h>
10#include <string.h>
11#include <unistd.h>
12#include "utils.h"
13#include "instructions.h"
14
15unsigned int expected_instruction = PPC_INST_COPY_FIRST;
16unsigned int instruction_mask = 0xfc2007fe;
17
18void signal_action_handler(int signal_num, siginfo_t *info, void *ptr)
19{
20 ucontext_t *ctx = ptr;
21#ifdef __powerpc64__
22 unsigned int *pc = (unsigned int *)ctx->uc_mcontext.gp_regs[PT_NIP];
23#else
24 unsigned int *pc = (unsigned int *)ctx->uc_mcontext.uc_regs->gregs[PT_NIP];
25#endif
26
27 /*
28 * Check that the signal was on the correct instruction, using a
29 * mask because the compiler assigns the register at RB.
30 */
31 if ((*pc & instruction_mask) == expected_instruction)
32 _exit(0); /* We hit the right instruction */
33
34 _exit(1);
35}
36
37void setup_signal_handler(void)
38{
39 struct sigaction signal_action;
40
41 memset(&signal_action, 0, sizeof(signal_action));
42 signal_action.sa_sigaction = signal_action_handler;
43 signal_action.sa_flags = SA_SIGINFO;
44 sigaction(SIGBUS, &signal_action, NULL);
45}
46
47char cacheline_buf[128] __cacheline_aligned;
48
49int test_copy_first_unaligned(void)
50{
51 /* Only run this test on a P9 or later */
52 SKIP_IF(!have_hwcap2(PPC_FEATURE2_ARCH_3_00));
53
54 /* Register our signal handler with SIGBUS */
55 setup_signal_handler();
56
57 /* +1 makes buf unaligned */
58 copy_first(cacheline_buf+1);
59
60 /* We should not get here */
61 return 1;
62}
63
64int main(int argc, char *argv[])
65{
66 return test_harness(test_copy_first_unaligned, "test_copy_first_unaligned");
67}