// SPDX-License-Identifier: GPL-2.0-only
|
/*
|
* Copyright 2015, Michael Neuling, IBM Corp.
|
*
|
* Test the kernel's signal delievery code to ensure that we don't
|
* trelaim twice in the kernel signal delivery code. This can happen
|
* if we trigger a signal when in a transaction and the stack pointer
|
* is bogus.
|
*
|
* This test case registers a SEGV handler, sets the stack pointer
|
* (r1) to NULL, starts a transaction and then generates a SEGV. The
|
* SEGV should be handled but we exit here as the stack pointer is
|
* invalid and hance we can't sigreturn. We only need to check that
|
* this flow doesn't crash the kernel.
|
*/
|
|
#include <unistd.h>
|
#include <sys/types.h>
|
#include <sys/wait.h>
|
#include <stdlib.h>
|
#include <stdio.h>
|
#include <signal.h>
|
|
#include "utils.h"
|
#include "tm.h"
|
|
void signal_segv(int signum)
|
{
|
/* This should never actually run since stack is foobar */
|
exit(1);
|
}
|
|
int tm_signal_stack()
|
{
|
int pid;
|
|
SKIP_IF(!have_htm());
|
|
pid = fork();
|
if (pid < 0)
|
exit(1);
|
|
if (pid) { /* Parent */
|
/*
|
* It's likely the whole machine will crash here so if
|
* the child ever exits, we are good.
|
*/
|
wait(NULL);
|
return 0;
|
}
|
|
/*
|
* The flow here is:
|
* 1) register a signal handler (so signal delievery occurs)
|
* 2) make stack pointer (r1) = NULL
|
* 3) start transaction
|
* 4) cause segv
|
*/
|
if (signal(SIGSEGV, signal_segv) == SIG_ERR)
|
exit(1);
|
asm volatile("li 1, 0 ;" /* stack ptr == NULL */
|
"1:"
|
"tbegin.;"
|
"beq 1b ;" /* retry forever */
|
"tsuspend.;"
|
"ld 2, 0(1) ;" /* trigger segv" */
|
: : : "memory");
|
|
/* This should never get here due to above segv */
|
return 1;
|
}
|
|
int main(void)
|
{
|
return test_harness(tm_signal_stack, "tm_signal_stack");
|
}
|
