cregit-Linux how code gets into the kernel

Release 4.10 tools/testing/selftests/powerpc/tm/tm-signal-msr-resv.c

/*
 * Copyright 2015, Michael Neuling, IBM Corp.
 * Licensed under GPLv2.
 *
 * 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); }

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michael neulingmichael neuling28100.00%1100.00%
Total28100.00%1100.00%


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; }

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michael neulingmichael neuling7097.22%150.00%
michael ellermanmichael ellerman22.78%150.00%
Total72100.00%2100.00%


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; }

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michael neulingmichael neuling87100.00%1100.00%
Total87100.00%1100.00%


int main(void) { return test_harness(tm_signal_msr_resv, "tm_signal_msr_resv"); }

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michael neulingmichael neuling15100.00%1100.00%
Total15100.00%1100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
michael neulingmichael neuling22499.12%150.00%
michael ellermanmichael ellerman20.88%150.00%
Total226100.00%2100.00%
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