1// SPDX-License-Identifier: GPL-2.0+
2
3/*
4 * Copyright 2018 IBM Corporation.
5 */
6
7#define __SANE_USERSPACE_TYPES__
8
9#include <sys/types.h>
10#include <stdint.h>
11#include <unistd.h>
12#include <signal.h>
13#include <stdlib.h>
14#include <string.h>
15#include <stdio.h>
16#include <sys/utsname.h>
17#include "reg.h"
18#include "utils.h"
19#include "flush_utils.h"
20
21static inline __u64 load(void *addr)
22{
23 __u64 tmp;
24
25 asm volatile("ld %0,0(%1)" : "=r"(tmp) : "b"(addr));
26
27 return tmp;
28}
29
30void syscall_loop(char *p, unsigned long iterations,
31 unsigned long zero_size)
32{
33 for (unsigned long i = 0; i < iterations; i++) {
34 for (unsigned long j = 0; j < zero_size; j += CACHELINE_SIZE)
35 load(p + j);
36 getppid();
37 }
38}
39
40void syscall_loop_uaccess(char *p, unsigned long iterations,
41 unsigned long zero_size)
42{
43 struct utsname utsname;
44
45 for (unsigned long i = 0; i < iterations; i++) {
46 for (unsigned long j = 0; j < zero_size; j += CACHELINE_SIZE)
47 load(p + j);
48 uname(&utsname);
49 }
50}
51
52static void sigill_handler(int signr, siginfo_t *info, void *unused)
53{
54 static int warned;
55 ucontext_t *ctx = (ucontext_t *)unused;
56 unsigned long *pc = &UCONTEXT_NIA(ctx);
57
58 /* mtspr 3,RS to check for move to DSCR below */
59 if ((*((unsigned int *)*pc) & 0xfc1fffff) == 0x7c0303a6) {
60 if (!warned++)
61 printf("WARNING: Skipping over dscr setup. Consider running 'ppc64_cpu --dscr=1' manually.\n");
62 *pc += 4;
63 } else {
64 printf("SIGILL at %p\n", pc);
65 abort();
66 }
67}
68
69void set_dscr(unsigned long val)
70{
71 static int init;
72 struct sigaction sa;
73
74 if (!init) {
75 memset(&sa, 0, sizeof(sa));
76 sa.sa_sigaction = sigill_handler;
77 sa.sa_flags = SA_SIGINFO;
78 if (sigaction(SIGILL, &sa, NULL))
79 perror("sigill_handler");
80 init = 1;
81 }
82
83 mtspr(SPRN_DSCR, val);
84}
85

source code of linux/tools/testing/selftests/powerpc/security/flush_utils.c