blob: 424ea685c2b7d485e6ff565e35798b2fcc0e14e3 [file] [log] [blame]
Richard Henderson36cd5fb2021-02-12 10:49:02 -08001/*
2 * Memory tagging, basic fail cases, asynchronous signals.
3 *
4 * Copyright (c) 2021 Linaro Ltd
5 * SPDX-License-Identifier: GPL-2.0-or-later
6 */
7
8#include "mte.h"
9
10void pass(int sig, siginfo_t *info, void *uc)
11{
12 assert(info->si_code == SEGV_MTEAERR);
13 exit(0);
14}
15
16int main(int ac, char **av)
17{
18 struct sigaction sa;
19 long *p0, *p1, *p2;
20 long excl = 1;
21
22 enable_mte(PR_MTE_TCF_ASYNC);
23 p0 = alloc_mte_mem(sizeof(*p0));
24
25 /* Create two differently tagged pointers. */
26 asm("irg %0,%1,%2" : "=r"(p1) : "r"(p0), "r"(excl));
27 asm("gmi %0,%1,%0" : "+r"(excl) : "r" (p1));
28 assert(excl != 1);
29 asm("irg %0,%1,%2" : "=r"(p2) : "r"(p0), "r"(excl));
30 assert(p1 != p2);
31
32 /* Store the tag from the first pointer. */
33 asm("stg %0, [%0]" : : "r"(p1));
34
35 *p1 = 0;
36
37 memset(&sa, 0, sizeof(sa));
38 sa.sa_sigaction = pass;
39 sa.sa_flags = SA_SIGINFO;
40 sigaction(SIGSEGV, &sa, NULL);
41
42 /*
43 * Signal for async error will happen eventually.
44 * For a real kernel this should be after the next IRQ (e.g. timer).
45 * For qemu linux-user, we kick the cpu and exit at the next TB.
46 * In either case, loop until this happens (or killed by timeout).
47 * For extra sauce, yield, producing EXCP_YIELD to cpu_loop().
48 */
49 asm("str %0, [%0]; yield" : : "r"(p2));
50 while (1);
51}