mirror of
				https://github.com/qemu/qemu.git
				synced 2025-10-31 12:07:31 +00:00 
			
		
		
		
	 36cd5fbdbf
			
		
	
	
		36cd5fbdbf
		
	
	
	
	
		
			
			Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org> Message-id: 20210212184902.1251044-32-richard.henderson@linaro.org Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
		
			
				
	
	
		
			52 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			52 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
 | |
|  * Memory tagging, basic fail cases, asynchronous signals.
 | |
|  *
 | |
|  * Copyright (c) 2021 Linaro Ltd
 | |
|  * SPDX-License-Identifier: GPL-2.0-or-later
 | |
|  */
 | |
| 
 | |
| #include "mte.h"
 | |
| 
 | |
| void pass(int sig, siginfo_t *info, void *uc)
 | |
| {
 | |
|     assert(info->si_code == SEGV_MTEAERR);
 | |
|     exit(0);
 | |
| }
 | |
| 
 | |
| int main(int ac, char **av)
 | |
| {
 | |
|     struct sigaction sa;
 | |
|     long *p0, *p1, *p2;
 | |
|     long excl = 1;
 | |
| 
 | |
|     enable_mte(PR_MTE_TCF_ASYNC);
 | |
|     p0 = alloc_mte_mem(sizeof(*p0));
 | |
| 
 | |
|     /* Create two differently tagged pointers.  */
 | |
|     asm("irg %0,%1,%2" : "=r"(p1) : "r"(p0), "r"(excl));
 | |
|     asm("gmi %0,%1,%0" : "+r"(excl) : "r" (p1));
 | |
|     assert(excl != 1);
 | |
|     asm("irg %0,%1,%2" : "=r"(p2) : "r"(p0), "r"(excl));
 | |
|     assert(p1 != p2);
 | |
| 
 | |
|     /* Store the tag from the first pointer.  */
 | |
|     asm("stg %0, [%0]" : : "r"(p1));
 | |
| 
 | |
|     *p1 = 0;
 | |
| 
 | |
|     memset(&sa, 0, sizeof(sa));
 | |
|     sa.sa_sigaction = pass;
 | |
|     sa.sa_flags = SA_SIGINFO;
 | |
|     sigaction(SIGSEGV, &sa, NULL);
 | |
| 
 | |
|     /*
 | |
|      * Signal for async error will happen eventually.
 | |
|      * For a real kernel this should be after the next IRQ (e.g. timer).
 | |
|      * For qemu linux-user, we kick the cpu and exit at the next TB.
 | |
|      * In either case, loop until this happens (or killed by timeout).
 | |
|      * For extra sauce, yield, producing EXCP_YIELD to cpu_loop().
 | |
|      */
 | |
|     asm("str %0, [%0]; yield" : : "r"(p2));
 | |
|     while (1);
 | |
| }
 |