1#!/bin/sh 2 3# 4# SPDX-License-Identifier: BSD-2-Clause 5# 6# Copyright (c) 2018 Dell EMC Isilon 7# 8# Redistribution and use in source and binary forms, with or without 9# modification, are permitted provided that the following conditions 10# are met: 11# 1. Redistributions of source code must retain the above copyright 12# notice, this list of conditions and the following disclaimer. 13# 2. Redistributions in binary form must reproduce the above copyright 14# notice, this list of conditions and the following disclaimer in the 15# documentation and/or other materials provided with the distribution. 16# 17# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20# ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27# SUCH DAMAGE. 28# 29 30# Bug 228858 - panic when delivering knote to a process who has opened a 31# kqueue() is dying 32# Page fault seen: https://people.freebsd.org/~pho/stress/log/mark052.txt 33# Fixed by r340897. 34 35# Test scenario based on analysis by siddharthtuli gmail com 36 37. ../default.cfg 38 39odir=`pwd` 40 41cd /tmp 42sed '1,/^EOF/d' < $odir/$0 > kevent12.c 43mycc -o kevent12 -Wall -Wextra -O2 -g kevent12.c || exit 1 44rm -f kevent12.c 45cd $odir 46 47(cd $odir/../testcases/swap; ./swap -t 5m -i 20 -l 100 > /dev/null 2>&1) & 48pid=$! 49/tmp/kevent12 50while pgrep -q swap; do 51 pkill -9 swap 52done 53wait $pid 54 55rm -f /tmp/kevent12 56exit 0 57EOF 58#include <sys/types.h> 59#include <sys/event.h> 60#include <sys/wait.h> 61 62#include <err.h> 63#include <errno.h> 64#include <signal.h> 65#include <stdio.h> 66#include <stdlib.h> 67#include <string.h> 68#include <time.h> 69#include <unistd.h> 70 71#define PARALLEL 64 72#define RUNTIME (5 * 60) 73 74static pid_t parent; 75static int kq; 76 77static void 78hand(int i __unused) { /* handler */ 79 kill(parent, SIGINT); 80 _exit(1); 81} 82 83static void 84init_kq() 85{ 86 kq = kqueue(); 87 if (kq == -1) 88 err(1, "kqueue"); 89} 90 91static void 92add_watch(pid_t pid) 93{ 94 struct kevent kev; 95 char msg[64]; 96 97 bzero(&kev, sizeof(kev)); 98 kev.ident = pid; 99 kev.flags = EV_ADD | EV_ENABLE; 100 kev.filter = EVFILT_PROC; 101 kev.fflags = NOTE_EXIT | NOTE_EXEC | NOTE_TRACK | NOTE_TRACKERR; 102 103 for (;;) { 104 int res = kevent(kq, &kev, 1, NULL, 0, NULL); 105 if (res == -1) { 106 if (errno == EINTR) 107 continue; 108 if (errno == ESRCH) 109 break; 110 111 snprintf(msg, sizeof(msg), 112 "kevent - add watch for pid %u", pid); 113 err(1, "%s", msg); 114 } 115 else 116 break; 117 } 118} 119 120static void 121polling() 122{ 123 struct kevent kev[10]; 124#if defined(DEBUG) 125 pid_t pid; 126 int i; 127#endif 128 129 for (;;) { 130 bzero(&kev, sizeof(kev)); 131 if (arc4random() % 100 < 10) { 132 signal(SIGALRM, hand); 133 ualarm(10000, 0); 134 } 135 int res = kevent(kq, NULL, 0, kev, 136 sizeof(kev) / sizeof(kev[0]), NULL); 137 if (res == -1) { 138 if (errno == EINTR) 139 continue; 140 141 if (errno == ESRCH) 142 continue; 143 144 err(1, "kevent"); 145 } 146 147#if defined(DEBUG) 148 for (i = 0; i < res; i++) { 149 pid = kev[i].ident; 150 if (kev[i].fflags & NOTE_CHILD) { 151 add_watch(pid); 152 printf("%u - new process, parent %u\n", pid, 153 (unsigned int)kev[i].data); 154 } 155 if (kev[i].fflags & NOTE_FORK) { 156 printf("%u forked\n", pid); 157 } 158 if (kev[i].fflags & NOTE_EXEC) { 159 printf("%u called exec\n", pid); 160 } 161 if (kev[i].fflags & NOTE_EXIT) { 162 printf("%u exited\n", pid); 163 if (parent == pid) 164 return; 165 } 166 if (kev[i].fflags & NOTE_TRACK) { 167 printf("%u forked - track\n", pid); 168 } 169 if (kev[i].fflags & NOTE_TRACKERR) { 170 fprintf(stderr, "%u - track error\n", pid); 171 } 172 } 173#endif 174 } 175} 176 177void 178churn(void) 179{ 180 pid_t pid; 181 time_t start; 182 char *cmdline[] = { "/usr/bin/true", NULL }; 183 184 start = time(NULL); 185 while (time(NULL) - start < RUNTIME) { 186 if ((pid = fork()) == -1) 187 err(1, "fork"); 188 if (pid == 0) { 189 if (execve(cmdline[0], cmdline, NULL) == -1) 190 err(1, "execve"); 191 } 192 if (waitpid(pid, NULL, 0) != pid) 193 err(1, "waitpid(%d):%d", pid, __LINE__); 194 } 195 196 _exit(0); 197} 198 199int 200test(void) 201{ 202 if ((parent = fork()) == 0) 203 churn(); 204 205 init_kq(); 206 add_watch(parent); 207 polling(); 208 if (waitpid(parent, NULL, 0) != parent) 209 err(1, "waitpid(%d):%d", parent, __LINE__); 210 211 _exit(0); 212} 213 214int 215main(void) 216{ 217 pid_t pids[PARALLEL]; 218 time_t start; 219 int i; 220 221 start = time(NULL); 222 while (time(NULL) - start < RUNTIME) { 223 for (i = 0; i < PARALLEL; i++) { 224 if ((pids[i] = fork()) == 0) 225 test(); 226 } 227 for (i = 0; i < PARALLEL; i++) 228 if (waitpid(pids[i], NULL, 0) != pids[i]) 229 err(1, "waitpid(%d):%d", pids[i], __LINE__); 230 } 231 232 return (0); 233} 234