#!/bin/sh
#
# Copyright (c) 2014 EMC Corp.
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
# SUCH DAMAGE.
#
# The issue makes it possible for applications to get wrong EINTR
# or ERESTART (the later is not directly visible) when doing write
# to the file on suspended UFS volume. I.e. the thread is sleeping
# when fs is suspended, and process is signaled.
# Test scenario mostly by kib.
# Fixed in r275744.
# Deadlock seen:
# https://people.freebsd.org/~pho/stress/log/pcatch.txt
[ `id -u ` -ne 0 ] && echo "Must be root!" && exit 1
[ -z "$DEBUG" ] && exit 0 # Waiting for fix
. ../default.cfg
here=`pwd`
cd /tmp
sed '1,/^EOF/d' < $here/$0 > pcatch.c
mycc -o pcatch -Wall -Wextra -O0 -g pcatch.c || exit 1
rm -f pcatch.c
cd $here
mount | grep -q "$mntpoint" && umount $mntpoint
mdconfig -l | grep -q $mdstart && mdconfig -d -u $mdstart
mdconfig -a -t swap -s 1g -u $mdstart
bsdlabel -w md$mdstart auto
newfs $newfs_flags md${mdstart}$part > /dev/null
mount /dev/md${mdstart}$part $mntpoint
start=`date '+%s'`
while [ $((`date '+%s'` - start)) -lt 120 ]; do
/tmp/pcatch $mntpoint
done
while mount | grep -q "on $mntpoint "; do
umount $mntpoint || sleep 1
done
mdconfig -d -u $mdstart
rm -f /tmp/pcatch
exit 0
EOF
#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/mount.h>
#include <sys/wait.h>
#include <ufs/ffs/fs.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
static void
hand_sigaction(int signo __unused, siginfo_t *si __unused, void *c __unused)
{
}
static void
suspend(char *path)
{
struct statfs s;
int fd, error;
if (fork() == 0) {
if ((error = statfs(path, &s)) != 0)
err(1, "statfs %s", path);
fd = open("/dev/ufssuspend", O_RDWR);
if ((error = ioctl(fd, UFSSUSPEND, &s.f_fsid)) != 0)
err(1, "UFSSUSPEND");
sleep(1);
if ((error = ioctl(fd, UFSRESUME, &s.f_fsid)) != 0)
err(1, "UFSRESUME");
_exit(0);
}
}
static void
test(char *mp)
{
pid_t pid;
struct sigaction sa;
int fd;
char buf[80], file[80];
memset(&sa, 0, sizeof(sa));
sa.sa_sigaction = hand_sigaction;
if (sigaction(SIGUSR1, &sa, NULL) == -1)
err(1, "sigaction");
snprintf(file, sizeof(file), "%s/file", mp);
if ((fd = open(file, O_RDWR | O_CREAT | O_TRUNC, 0640)) == -1)
err(1, "open(%s). %s:%d", file, __FILE__, __LINE__);
suspend(mp);
if ((pid = fork()) == 0) {
if (write(fd, buf, sizeof(buf)) == -1)
warn("FAIL: write");
_exit(0);
}
usleep(10000);
if (kill(pid, SIGUSR1) == -1)
err(1, "kill");
wait(NULL);
wait(NULL);
close(fd);
}
int
main(int argc, char *argv[])
{
if (argc != 2)
errx(1, "Usage: %s <UFS mount point>", argv[0]);
test(argv[1]);
return (0);
}
