linux/linux-5.4.31/tools/testing/selftests/powerpc/tm/tm-signal-msr-resv.c

75 lines
1.7 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright 2015, Michael Neuling, IBM Corp.
*
* Test the kernel's signal return code to ensure that it doesn't
* crash when both the transactional and suspend MSR bits are set in
* the signal context.
*
* For this test, we send ourselves a SIGUSR1. In the SIGUSR1 handler
* we modify the signal context to set both MSR TM S and T bits (which
* is "reserved" by the PowerISA). When we return from the signal
* handler (implicit sigreturn), the kernel should detect reserved MSR
* value and send us with a SIGSEGV.
*/
#include <stdlib.h>
#include <stdio.h>
#include <signal.h>
#include <unistd.h>
#include "utils.h"
#include "tm.h"
int segv_expected = 0;
void signal_segv(int signum)
{
if (segv_expected && (signum == SIGSEGV))
_exit(0);
_exit(1);
}
void signal_usr1(int signum, siginfo_t *info, void *uc)
{
ucontext_t *ucp = uc;
/* Link tm checkpointed context to normal context */
ucp->uc_link = ucp;
/* Set all TM bits so that the context is now invalid */
#ifdef __powerpc64__
ucp->uc_mcontext.gp_regs[PT_MSR] |= (7ULL << 32);
#else
ucp->uc_mcontext.uc_regs->gregs[PT_MSR] |= (7ULL);
#endif
/* Should segv on return becuase of invalid context */
segv_expected = 1;
}
int tm_signal_msr_resv()
{
struct sigaction act;
SKIP_IF(!have_htm());
act.sa_sigaction = signal_usr1;
sigemptyset(&act.sa_mask);
act.sa_flags = SA_SIGINFO;
if (sigaction(SIGUSR1, &act, NULL) < 0) {
perror("sigaction sigusr1");
exit(1);
}
if (signal(SIGSEGV, signal_segv) == SIG_ERR)
exit(1);
raise(SIGUSR1);
/* We shouldn't get here as we exit in the segv handler */
return 1;
}
int main(void)
{
return test_harness(tm_signal_msr_resv, "tm_signal_msr_resv");
}