1 /*
2 * Copyright (c) International Business Machines Corp., 2008
3 * Copyright (c) Paul Mackerras, IBM Corp., 2008
4 * Copyright (c) 2018 Linux Test Project
5 *
6 * This program is free software: you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation, either version 3 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
18 */
19
20 /*
21 * Test little-endian mode switch system call. Requires a 64-bit
22 * processor that supports little-endian mode,such as POWER6.
23 */
24
25 #include <errno.h>
26 #include <stdio.h>
27 #include <stdlib.h>
28 #include <unistd.h>
29 #include <elf.h>
30 #include <sys/types.h>
31 #include <sys/wait.h>
32 #include "tst_test.h"
33
34 #if defined (__powerpc64__) || (__powerpc__)
35 # ifndef PPC_FEATURE_TRUE_LE
36 # define PPC_FEATURE_TRUE_LE 0x00000002
37 # endif
38
39 # define TST_NO_DEFAULT_MAIN
40
41 /*
42 * Make minimal call to 0x1ebe. If we get ENOSYS then syscall is not
43 * available, likely because of:
44 * commit 727f13616c45 ("powerpc: Disable the fast-endian switch syscall by default")
45 * If we get any other outcome, including crashes with various signals,
46 * then we assume syscall is available and carry on with the test.
47 */
check_le_switch_supported(void)48 void check_le_switch_supported(void)
49 {
50 int status;
51
52 if (SAFE_FORK() == 0) {
53 syscall(0x1ebe);
54 exit(errno);
55 }
56
57 SAFE_WAIT(&status);
58 if (WIFSIGNALED(status)) {
59 int sig = WTERMSIG(status);
60
61 tst_res(TINFO, "check exited with sig %d", sig);
62 } else if (WIFEXITED(status)) {
63 int rc = WEXITSTATUS(status);
64
65 tst_res(TINFO, "check exited with %d", rc);
66 if (rc == ENOSYS)
67 tst_brk(TCONF, "fast endian switch (0x1ebe) N/A");
68 }
69 }
70
test_le_switch(void)71 void test_le_switch(void)
72 {
73 int status;
74
75 if (SAFE_FORK() == 0) {
76 register int r0 asm("r0") = 0x1ebe;
77
78 asm volatile ("sc; .long 0x02000044"
79 : "=&r" (r0)
80 : "0"(r0)
81 : "cr0", "r9", "r10", "r11", "r12");
82 exit(0);
83 }
84
85 SAFE_WAIT(&status);
86 if (WIFSIGNALED(status)) {
87 int sig = WTERMSIG(status);
88
89 tst_res(TFAIL, "test exited with sig %d", sig);
90 } else if (WIFEXITED(status)) {
91 int rc = WEXITSTATUS(status);
92
93 if (rc != 0)
94 tst_res(TFAIL, "test exited with %d", rc);
95 else
96 tst_res(TPASS, "endian_switch() syscall tests passed");
97 }
98 }
99
endian_test(void)100 static void endian_test(void)
101 {
102 check_le_switch_supported();
103 test_le_switch();
104 }
105
106 static struct tst_test test = {
107 .test_all = endian_test,
108 .min_kver = "2.6.26",
109 .forks_child = 1,
110 };
111
main4(int argc,char ** argv,LTP_ATTRIBUTE_UNUSED char ** envp,unsigned long * auxv)112 int main4(int argc, char **argv, LTP_ATTRIBUTE_UNUSED char **envp,
113 unsigned long *auxv)
114 {
115 for (; *auxv != AT_NULL && *auxv != AT_HWCAP; auxv += 2)
116 ;
117
118 if (!(auxv[0] == AT_HWCAP && (auxv[1] & PPC_FEATURE_TRUE_LE)))
119 tst_brk(TCONF, "Processor does not support little-endian mode");
120
121 tst_run_tcases(argc, argv, &test);
122 return 0;
123 }
124
125 #else /* defined (__powerpc64__) || (__powerpc__) */
126 TST_TEST_TCONF("This system does not support running of switch() syscall");
127 #endif
128