/*
* libhugetlbfs - Easy use of Linux hugepages
* Copyright (C) 2005-2006 David Gibson & Adam Litke, IBM Corporation.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License
* as published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <signal.h>
#include <sys/mman.h>
#include <hugetlbfs.h>
#include "hugetests.h"
/*
* Test rationale:
*
* Some kernel have a bug in the positioning of the test against
* i_size. This bug means that attempting to instantiate a page
* beyond the end of a hugepage file can result in an OOM and SIGKILL
* instead of the correct SIGBUS.
*
* This bug was fixed by commit ebed4bfc8da8df5b6b0bc4a5064a949f04683509.
*/
static void sigbus_handler(int signum, siginfo_t *si, void *uc)
{
PASS();
}
int main(int argc, char *argv[])
{
long hpage_size;
int fd, fdx;
unsigned long totpages;
void *p, *q;
int i;
int err;
struct sigaction sa = {
.sa_sigaction = sigbus_handler,
.sa_flags = SA_SIGINFO,
};
test_init(argc, argv);
hpage_size = check_hugepagesize();
totpages = get_huge_page_counter(hpage_size, HUGEPAGES_TOTAL);
fd = hugetlbfs_unlinked_fd();
if (fd < 0)
FAIL("hugetlbfs_unlinked_fd()");
p = mmap(NULL, hpage_size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
if (p == MAP_FAILED)
FAIL("mmap(): %s", strerror(errno));
err = ftruncate(fd, 0);
if (err)
FAIL("ftruncate(): %s", strerror(errno));
/* Now slurp up all the available pages */
fdx = hugetlbfs_unlinked_fd();
if (fdx < 0)
FAIL("hugetlbfs_unlinked_fd() 2");
q = mmap(NULL, totpages * hpage_size, PROT_READ|PROT_WRITE, MAP_SHARED,
fdx, 0);
if (q == MAP_FAILED)
FAIL("mmap() reserving all pages: %s", strerror(errno));
/* Touch the pages to ensure they're removed from the pool */
for (i = 0; i < totpages; i++) {
volatile char *x = (volatile char *)q + i*hpage_size;
*x = 0;
}
/* SIGBUS is what *should* happen */
err = sigaction(SIGBUS, &sa, NULL);
if (err)
FAIL("sigaction(): %s", strerror(errno));
*((volatile unsigned int *)p);
/* Should have SIGBUSed above, or (failed the test) with SIGKILL */
FAIL("Didn't SIGBUS or OOM");
}