xref: /OK3568_Linux_fs/kernel/tools/testing/selftests/powerpc/tm/tm-signal-msr-resv.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * Copyright 2015, Michael Neuling, IBM Corp.
4*4882a593Smuzhiyun  *
5*4882a593Smuzhiyun  * Test the kernel's signal return code to ensure that it doesn't
6*4882a593Smuzhiyun  * crash when both the transactional and suspend MSR bits are set in
7*4882a593Smuzhiyun  * the signal context.
8*4882a593Smuzhiyun  *
9*4882a593Smuzhiyun  * For this test, we send ourselves a SIGUSR1.  In the SIGUSR1 handler
10*4882a593Smuzhiyun  * we modify the signal context to set both MSR TM S and T bits (which
11*4882a593Smuzhiyun  * is "reserved" by the PowerISA). When we return from the signal
12*4882a593Smuzhiyun  * handler (implicit sigreturn), the kernel should detect reserved MSR
13*4882a593Smuzhiyun  * value and send us with a SIGSEGV.
14*4882a593Smuzhiyun  */
15*4882a593Smuzhiyun 
16*4882a593Smuzhiyun #include <stdlib.h>
17*4882a593Smuzhiyun #include <stdio.h>
18*4882a593Smuzhiyun #include <signal.h>
19*4882a593Smuzhiyun #include <unistd.h>
20*4882a593Smuzhiyun 
21*4882a593Smuzhiyun #include "utils.h"
22*4882a593Smuzhiyun #include "tm.h"
23*4882a593Smuzhiyun 
24*4882a593Smuzhiyun int segv_expected = 0;
25*4882a593Smuzhiyun 
signal_segv(int signum)26*4882a593Smuzhiyun void signal_segv(int signum)
27*4882a593Smuzhiyun {
28*4882a593Smuzhiyun 	if (segv_expected && (signum == SIGSEGV))
29*4882a593Smuzhiyun 		_exit(0);
30*4882a593Smuzhiyun 	_exit(1);
31*4882a593Smuzhiyun }
32*4882a593Smuzhiyun 
signal_usr1(int signum,siginfo_t * info,void * uc)33*4882a593Smuzhiyun void signal_usr1(int signum, siginfo_t *info, void *uc)
34*4882a593Smuzhiyun {
35*4882a593Smuzhiyun 	ucontext_t *ucp = uc;
36*4882a593Smuzhiyun 
37*4882a593Smuzhiyun 	/* Link tm checkpointed context to normal context */
38*4882a593Smuzhiyun 	ucp->uc_link = ucp;
39*4882a593Smuzhiyun 	/* Set all TM bits so that the context is now invalid */
40*4882a593Smuzhiyun #ifdef __powerpc64__
41*4882a593Smuzhiyun 	ucp->uc_mcontext.gp_regs[PT_MSR] |= (7ULL << 32);
42*4882a593Smuzhiyun #else
43*4882a593Smuzhiyun 	ucp->uc_mcontext.uc_regs->gregs[PT_MSR] |= (7ULL);
44*4882a593Smuzhiyun #endif
45*4882a593Smuzhiyun 	/* Should segv on return becuase of invalid context */
46*4882a593Smuzhiyun 	segv_expected = 1;
47*4882a593Smuzhiyun }
48*4882a593Smuzhiyun 
tm_signal_msr_resv()49*4882a593Smuzhiyun int tm_signal_msr_resv()
50*4882a593Smuzhiyun {
51*4882a593Smuzhiyun 	struct sigaction act;
52*4882a593Smuzhiyun 
53*4882a593Smuzhiyun 	SKIP_IF(!have_htm());
54*4882a593Smuzhiyun 
55*4882a593Smuzhiyun 	act.sa_sigaction = signal_usr1;
56*4882a593Smuzhiyun 	sigemptyset(&act.sa_mask);
57*4882a593Smuzhiyun 	act.sa_flags = SA_SIGINFO;
58*4882a593Smuzhiyun 	if (sigaction(SIGUSR1, &act, NULL) < 0) {
59*4882a593Smuzhiyun 		perror("sigaction sigusr1");
60*4882a593Smuzhiyun 		exit(1);
61*4882a593Smuzhiyun 	}
62*4882a593Smuzhiyun 	if (signal(SIGSEGV, signal_segv) == SIG_ERR)
63*4882a593Smuzhiyun 		exit(1);
64*4882a593Smuzhiyun 
65*4882a593Smuzhiyun 	raise(SIGUSR1);
66*4882a593Smuzhiyun 
67*4882a593Smuzhiyun 	/* We shouldn't get here as we exit in the segv handler */
68*4882a593Smuzhiyun 	return 1;
69*4882a593Smuzhiyun }
70*4882a593Smuzhiyun 
main(void)71*4882a593Smuzhiyun int main(void)
72*4882a593Smuzhiyun {
73*4882a593Smuzhiyun 	return test_harness(tm_signal_msr_resv, "tm_signal_msr_resv");
74*4882a593Smuzhiyun }
75