1 /* 2 * Stack size mapping is decreased through mlock/munlock call. 3 * 4 * This is to test kernel if it has a problem with shortening [stack] 5 * mapping through several loops of mlock/munlock of /proc/self/maps. 6 * 7 * From: 8 * munlock 76KiB bfef2000-bff05000 rw-p 00000000 00:00 0 [stack] 9 * 10 * To: 11 * munlock 44KiB bfefa000-bff05000 rw-p 00000000 00:00 0 [stack] 12 * 13 * with more iterations - could drop to 0KiB. 14 * 15 * Copyright (C) 2010 Red Hat, Inc. 16 * This program is free software; you can redistribute it and/or 17 * modify it under the terms of version 2 of the GNU General Public 18 * License as published by the Free Software Foundation. 19 * 20 * This program is distributed in the hope that it would be useful, 21 * but WITHOUT ANY WARRANTY; without even the implied warranty of 22 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 23 * 24 * Further, this software is distributed without any warranty that it 25 * is free of the rightful claim of any third person regarding 26 * infringement or the like. Any license provided herein, whether 27 * implied or otherwise, applies only to this software file. Patent 28 * licenses, if any, provided herein do not apply to combinations of 29 * this program with other software, or any other product whatsoever. 30 * 31 * You should have received a copy of the GNU General Public License 32 * along with this program; if not, write the Free Software 33 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 34 * 02110-1301, USA. 35 */ 36 #include <sys/mman.h> 37 #include <stdio.h> 38 #include <string.h> 39 #include "test.h" 40 41 #define KB 1024 42 43 char *TCID = "mlock03"; 44 int TST_TOTAL = 1; 45 46 static void setup(void); 47 static void cleanup(void); 48 49 int main(int argc, char *argv[]) 50 { 51 int lc; 52 long from, to; 53 long first = -1, last = -1; 54 char b[KB]; 55 FILE *fp; 56 57 tst_parse_opts(argc, argv, NULL, NULL); 58 59 setup(); 60 61 for (lc = 0; TEST_LOOPING(lc); lc++) { 62 fp = fopen("/proc/self/maps", "r"); 63 if (fp == NULL) 64 tst_brkm(TBROK | TERRNO, cleanup, "fopen"); 65 while (!feof(fp)) { 66 if (!fgets(b, KB - 1, fp)) 67 break; 68 b[strlen(b) - 1] = '\0'; 69 sscanf(b, "%lx-%lx", &from, &to); 70 71 /* Record the initial stack size. */ 72 if (lc == 0 && strstr(b, "[stack]") != NULL) 73 first = (to - from) / KB; 74 75 switch (lc & 1) { 76 case 0: 77 if (mlock((const void *)from, to - from) == -1) 78 tst_resm(TINFO | TERRNO, 79 "mlock failed"); 80 break; 81 case 1: 82 if (munlock((void *)from, to - from) == -1) 83 tst_resm(TINFO | TERRNO, 84 "munlock failed"); 85 break; 86 default: 87 break; 88 } 89 tst_resm(TINFO, "%s from %lx to %0lx", 90 (lc & 1) ? "munlock" : "mlock", from, to); 91 92 /* Record the final stack size. */ 93 if (strstr(b, "[stack]") != NULL) 94 last = (to - from) / KB; 95 } 96 fclose(fp); 97 } 98 tst_resm(TINFO, "starting stack size is %ld", first); 99 tst_resm(TINFO, "final stack size is %ld", last); 100 if (last < first) 101 tst_resm(TFAIL, "stack size is decreased."); 102 else 103 tst_resm(TPASS, "stack size is not decreased."); 104 105 cleanup(); 106 tst_exit(); 107 } 108 109 void setup(void) 110 { 111 tst_require_root(); 112 113 tst_sig(FORK, DEF_HANDLER, cleanup); 114 TEST_PAUSE; 115 } 116 117 void cleanup(void) 118 { 119 } 120