tools/testing/selftests/kmod/kmod.sh

   1 #!/bin/bash
   2 #
   3 # Copyright (C) 2017 Luis R. Rodriguez <mcgrof@kernel.org>
   4 #
   5 # This program is free software; you can redistribute it and/or modify it
   6 # under the terms of the GNU General Public License as published by the Free
   7 # Software Foundation; either version 2 of the License, or at your option any
   8 # later version; or, when distributed separately from the Linux kernel or
   9 # when incorporated into other software packages, subject to the following
  10 # license:
  11 #
  12 # This program is free software; you can redistribute it and/or modify it
  13 # under the terms of copyleft-next (version 0.3.1 or later) as published
  14 # at http://copyleft-next.org/.
  15
  16 # This is a stress test script for kmod, the kernel module loader. It uses
  17 # test_kmod which exposes a series of knobs for the API for us so we can
  18 # tweak each test in userspace rather than in kernelspace.
  19 #
  20 # The way kmod works is it uses the kernel's usermode helper API to eventually
  21 # call /sbin/modprobe. It has a limit of the number of concurrent calls
  22 # possible. The kernel interface to load modules is request_module(), however
  23 # mount uses get_fs_type(). Both behave slightly differently, but the
  24 # differences are important enough to test each call separately. For this
  25 # reason test_kmod starts by providing tests for both calls.
  26 #
  27 # The test driver test_kmod assumes a series of defaults which you can
  28 # override by exporting to your environment prior running this script.
  29 # For instance this script assumes you do not have xfs loaded upon boot.
  30 # If this is false, export DEFAULT_KMOD_FS="ext4" prior to running this
  31 # script if the filesystem module you don't have loaded upon bootup
  32 # is ext4 instead. Refer to allow_user_defaults() for a list of user
  33 # override variables possible.
  34 #
  35 # You'll want at least 4 GiB of RAM to expect to run these tests
  36 # without running out of memory on them. For other requirements refer
  37 # to test_reqs()
  38
  39 set -e
  40
  41 TEST_NAME="kmod"
  42 TEST_DRIVER="test_${TEST_NAME}"
  43 TEST_DIR=$(dirname $0)
  44
  45 # This represents
  46 #
  47 # TEST_ID:TEST_COUNT:ENABLED
  48 #
  49 # TEST_ID: is the test id number
  50 # TEST_COUNT: number of times we should run the test
  51 # ENABLED: 1 if enabled, 0 otherwise
  52 #
  53 # Once these are enabled please leave them as-is. Write your own test,
  54 # we have tons of space.
  55 ALL_TESTS="0001:3:1"
  56 ALL_TESTS="$ALL_TESTS 0002:3:1"
  57 ALL_TESTS="$ALL_TESTS 0003:1:1"
  58 ALL_TESTS="$ALL_TESTS 0004:1:1"
  59 ALL_TESTS="$ALL_TESTS 0005:10:1"
  60 ALL_TESTS="$ALL_TESTS 0006:10:1"
  61 ALL_TESTS="$ALL_TESTS 0007:5:1"
  62 ALL_TESTS="$ALL_TESTS 0008:150:1"
  63 ALL_TESTS="$ALL_TESTS 0009:150:1"
  64 ALL_TESTS="$ALL_TESTS 0010:1:1"
  65 ALL_TESTS="$ALL_TESTS 0011:1:1"
  66 ALL_TESTS="$ALL_TESTS 0012:1:1"
  67 ALL_TESTS="$ALL_TESTS 0013:1:1"
  68
  69 # Kselftest framework requirement - SKIP code is 4.
  70 ksft_skip=4
  71
  72 test_modprobe()
  73 {
  74        if [ ! -d $DIR ]; then
  75                echo "$0: $DIR not present" >&2
  76                echo "You must have the following enabled in your kernel:" >&2
  77                cat $TEST_DIR/config >&2
  78                exit $ksft_skip
  79        fi
  80 }
  81
  82 function allow_user_defaults()
  83 {
  84         if [ -z $DEFAULT_KMOD_DRIVER ]; then
  85                 DEFAULT_KMOD_DRIVER="test_module"
  86         fi
  87
  88         if [ -z $DEFAULT_KMOD_FS ]; then
  89                 DEFAULT_KMOD_FS="xfs"
  90         fi
  91
  92         if [ -z $PROC_DIR ]; then
  93                 PROC_DIR="/proc/sys/kernel/"
  94         fi
  95
  96         if [ -z $MODPROBE_LIMIT ]; then
  97                 MODPROBE_LIMIT=50
  98         fi
  99
 100         if [ -z $DIR ]; then
 101                 DIR="/sys/devices/virtual/misc/${TEST_DRIVER}0/"
 102         fi
 103
 104         if [ -z $DEFAULT_NUM_TESTS ]; then
 105                 DEFAULT_NUM_TESTS=150
 106         fi
 107
 108         MODPROBE_LIMIT_FILE="${PROC_DIR}/kmod-limit"
 109 }
 110
 111 test_reqs()
 112 {
 113         if ! which modprobe 2> /dev/null > /dev/null; then
 114                 echo "$0: You need modprobe installed" >&2
 115                 exit $ksft_skip
 116         fi
 117
 118         if ! which kmod 2> /dev/null > /dev/null; then
 119                 echo "$0: You need kmod installed" >&2
 120                 exit $ksft_skip
 121         fi
 122
 123         # kmod 19 has a bad bug where it returns 0 when modprobe
 124         # gets called *even* if the module was not loaded due to
 125         # some bad heuristics. For details see:
 126         #
 127         # A work around is possible in-kernel but its rather
 128         # complex.
 129         KMOD_VERSION=$(kmod --version | awk '{print $3}')
 130         if [[ $KMOD_VERSION  -le 19 ]]; then
 131                 echo "$0: You need at least kmod 20" >&2
 132                 echo "kmod <= 19 is buggy, for details see:" >&2
 133                 echo "https://git.kernel.org/cgit/utils/kernel/kmod/kmod.git/commit/libkmod/libkmod-module.c?id=fd44a98ae2eb5eb32161088954ab21e58e19dfc4" >&2
 134                 exit $ksft_skip
 135         fi
 136
 137         uid=$(id -u)
 138         if [ $uid -ne 0 ]; then
 139                 echo $msg must be run as root >&2
 140                 exit $ksft_skip
 141         fi
 142 }
 143
 144 function load_req_mod()
 145 {
 146         trap "test_modprobe" EXIT
 147
 148         if [ ! -d $DIR ]; then
 149                 # Alanis: "Oh isn't it ironic?"
 150                 modprobe $TEST_DRIVER
 151         fi
 152 }
 153
 154 test_finish()
 155 {
 156         echo "$MODPROBE" > /proc/sys/kernel/modprobe
 157         echo "Test completed"
 158 }
 159
 160 errno_name_to_val()
 161 {
 162         case "$1" in
 163         # kmod calls modprobe and upon of a module not found
 164         # modprobe returns just 1... However in the kernel we
 165         # *sometimes* see 256...
 166         MODULE_NOT_FOUND)
 167                 echo 256;;
 168         SUCCESS)
 169                 echo 0;;
 170         -EPERM)
 171                 echo -1;;
 172         -ENOENT)
 173                 echo -2;;
 174         -EINVAL)
 175                 echo -22;;
 176         -ERR_ANY)
 177                 echo -123456;;
 178         *)
 179                 echo invalid;;
 180         esac
 181 }
 182
 183 errno_val_to_name()
 184         case "$1" in
 185         256)
 186                 echo MODULE_NOT_FOUND;;
 187         0)
 188                 echo SUCCESS;;
 189         -1)
 190                 echo -EPERM;;
 191         -2)
 192                 echo -ENOENT;;
 193         -22)
 194                 echo -EINVAL;;
 195         -123456)
 196                 echo -ERR_ANY;;
 197         *)
 198                 echo invalid;;
 199         esac
 200
 201 config_set_test_case_driver()
 202 {
 203         if ! echo -n 1 >$DIR/config_test_case; then
 204                 echo "$0: Unable to set to test case to driver" >&2
 205                 exit 1
 206         fi
 207 }
 208
 209 config_set_test_case_fs()
 210 {
 211         if ! echo -n 2 >$DIR/config_test_case; then
 212                 echo "$0: Unable to set to test case to fs" >&2
 213                 exit 1
 214         fi
 215 }
 216
 217 config_num_threads()
 218 {
 219         if ! echo -n $1 >$DIR/config_num_threads; then
 220                 echo "$0: Unable to set to number of threads" >&2
 221                 exit 1
 222         fi
 223 }
 224
 225 config_get_modprobe_limit()
 226 {
 227         if [[ -f ${MODPROBE_LIMIT_FILE} ]] ; then
 228                 MODPROBE_LIMIT=$(cat $MODPROBE_LIMIT_FILE)
 229         fi
 230         echo $MODPROBE_LIMIT
 231 }
 232
 233 config_num_thread_limit_extra()
 234 {
 235         MODPROBE_LIMIT=$(config_get_modprobe_limit)
 236         let EXTRA_LIMIT=$MODPROBE_LIMIT+$1
 237         config_num_threads $EXTRA_LIMIT
 238 }
 239
 240 # For special characters use printf directly,
 241 # refer to kmod_test_0001
 242 config_set_driver()
 243 {
 244         if ! echo -n $1 >$DIR/config_test_driver; then
 245                 echo "$0: Unable to set driver" >&2
 246                 exit 1
 247         fi
 248 }
 249
 250 config_set_fs()
 251 {
 252         if ! echo -n $1 >$DIR/config_test_fs; then
 253                 echo "$0: Unable to set driver" >&2
 254                 exit 1
 255         fi
 256 }
 257
 258 config_get_driver()
 259 {
 260         cat $DIR/config_test_driver
 261 }
 262
 263 config_get_test_result()
 264 {
 265         cat $DIR/test_result
 266 }
 267
 268 config_reset()
 269 {
 270         if ! echo -n "1" >"$DIR"/reset; then
 271                 echo "$0: reset should have worked" >&2
 272                 exit 1
 273         fi
 274 }
 275
 276 config_show_config()
 277 {
 278         echo "----------------------------------------------------"
 279         cat "$DIR"/config
 280         echo "----------------------------------------------------"
 281 }
 282
 283 config_trigger()
 284 {
 285         if ! echo -n "1" >"$DIR"/trigger_config 2>/dev/null; then
 286                 echo "$1: FAIL - loading should have worked"
 287                 config_show_config
 288                 exit 1
 289         fi
 290         echo "$1: OK! - loading kmod test"
 291 }
 292
 293 config_trigger_want_fail()
 294 {
 295         if echo "1" > $DIR/trigger_config 2>/dev/null; then
 296                 echo "$1: FAIL - test case was expected to fail"
 297                 config_show_config
 298                 exit 1
 299         fi
 300         echo "$1: OK! - kmod test case failed as expected"
 301 }
 302
 303 config_expect_result()
 304 {
 305         RC=$(config_get_test_result)
 306         RC_NAME=$(errno_val_to_name $RC)
 307
 308         ERRNO_NAME=$2
 309         ERRNO=$(errno_name_to_val $ERRNO_NAME)
 310
 311         if [[ $ERRNO_NAME = "-ERR_ANY" ]]; then
 312                 if [[ $RC -ge 0 ]]; then
 313                         echo "$1: FAIL, test expects $ERRNO_NAME - got $RC_NAME ($RC)" >&2
 314                         config_show_config
 315                         exit 1
 316                 fi
 317         elif [[ $RC != $ERRNO ]]; then
 318                 echo "$1: FAIL, test expects $ERRNO_NAME ($ERRNO) - got $RC_NAME ($RC)" >&2
 319                 config_show_config
 320                 exit 1
 321         fi
 322         echo "$1: OK! - Return value: $RC ($RC_NAME), expected $ERRNO_NAME"
 323 }
 324
 325 kmod_defaults_driver()
 326 {
 327         config_reset
 328         modprobe -r $DEFAULT_KMOD_DRIVER
 329         config_set_driver $DEFAULT_KMOD_DRIVER
 330 }
 331
 332 kmod_defaults_fs()
 333 {
 334         config_reset
 335         modprobe -r $DEFAULT_KMOD_FS
 336         config_set_fs $DEFAULT_KMOD_FS
 337         config_set_test_case_fs
 338 }
 339
 340 kmod_test_0001_driver()
 341 {
 342         NAME='\000'
 343
 344         kmod_defaults_driver
 345         config_num_threads 1
 346         printf $NAME >"$DIR"/config_test_driver
 347         config_trigger ${FUNCNAME[0]}
 348         config_expect_result ${FUNCNAME[0]} MODULE_NOT_FOUND
 349 }
 350
 351 kmod_test_0001_fs()
 352 {
 353         NAME='\000'
 354
 355         kmod_defaults_fs
 356         config_num_threads 1
 357         printf $NAME >"$DIR"/config_test_fs
 358         config_trigger ${FUNCNAME[0]}
 359         config_expect_result ${FUNCNAME[0]} -EINVAL
 360 }
 361
 362 kmod_test_0001()
 363 {
 364         kmod_test_0001_driver
 365         kmod_test_0001_fs
 366 }
 367
 368 kmod_test_0002_driver()
 369 {
 370         NAME="nope-$DEFAULT_KMOD_DRIVER"
 371
 372         kmod_defaults_driver
 373         config_set_driver $NAME
 374         config_num_threads 1
 375         config_trigger ${FUNCNAME[0]}
 376         config_expect_result ${FUNCNAME[0]} MODULE_NOT_FOUND
 377 }
 378
 379 kmod_test_0002_fs()
 380 {
 381         NAME="nope-$DEFAULT_KMOD_FS"
 382
 383         kmod_defaults_fs
 384         config_set_fs $NAME
 385         config_trigger ${FUNCNAME[0]}
 386         config_expect_result ${FUNCNAME[0]} -EINVAL
 387 }
 388
 389 kmod_test_0002()
 390 {
 391         kmod_test_0002_driver
 392         kmod_test_0002_fs
 393 }
 394
 395 kmod_test_0003()
 396 {
 397         kmod_defaults_fs
 398         config_num_threads 1
 399         config_trigger ${FUNCNAME[0]}
 400         config_expect_result ${FUNCNAME[0]} SUCCESS
 401 }
 402
 403 kmod_test_0004()
 404 {
 405         kmod_defaults_fs
 406         config_num_threads 2
 407         config_trigger ${FUNCNAME[0]}
 408         config_expect_result ${FUNCNAME[0]} SUCCESS
 409 }
 410
 411 kmod_test_0005()
 412 {
 413         kmod_defaults_driver
 414         config_trigger ${FUNCNAME[0]}
 415         config_expect_result ${FUNCNAME[0]} SUCCESS
 416 }
 417
 418 kmod_test_0006()
 419 {
 420         kmod_defaults_fs
 421         config_trigger ${FUNCNAME[0]}
 422         config_expect_result ${FUNCNAME[0]} SUCCESS
 423 }
 424
 425 kmod_test_0007()
 426 {
 427         kmod_test_0005
 428         kmod_test_0006
 429 }
 430
 431 kmod_test_0008()
 432 {
 433         kmod_defaults_driver
 434         MODPROBE_LIMIT=$(config_get_modprobe_limit)
 435         let EXTRA=$MODPROBE_LIMIT/6
 436         config_num_thread_limit_extra $EXTRA
 437         config_trigger ${FUNCNAME[0]}
 438         config_expect_result ${FUNCNAME[0]} SUCCESS
 439 }
 440
 441 kmod_test_0009()
 442 {
 443         kmod_defaults_fs
 444         MODPROBE_LIMIT=$(config_get_modprobe_limit)
 445         let EXTRA=$MODPROBE_LIMIT/4
 446         config_num_thread_limit_extra $EXTRA
 447         config_trigger ${FUNCNAME[0]}
 448         config_expect_result ${FUNCNAME[0]} SUCCESS
 449 }
 450
 451 kmod_test_0010()
 452 {
 453         kmod_defaults_driver
 454         config_num_threads 1
 455         echo "/KMOD_TEST_NONEXISTENT" > /proc/sys/kernel/modprobe
 456         config_trigger ${FUNCNAME[0]}
 457         config_expect_result ${FUNCNAME[0]} -ENOENT
 458         echo "$MODPROBE" > /proc/sys/kernel/modprobe
 459 }
 460
 461 kmod_test_0011()
 462 {
 463         kmod_defaults_driver
 464         config_num_threads 1
 465         # This causes the kernel to not even try executing modprobe.  The error
 466         # code is still -ENOENT like when modprobe doesn't exist, so we can't
 467         # easily test for the exact difference.  But this still is a useful test
 468         # since there was a bug where request_module() returned 0 in this case.
 469         echo > /proc/sys/kernel/modprobe
 470         config_trigger ${FUNCNAME[0]}
 471         config_expect_result ${FUNCNAME[0]} -ENOENT
 472         echo "$MODPROBE" > /proc/sys/kernel/modprobe
 473 }
 474
 475 kmod_check_visibility()
 476 {
 477         local name="$1"
 478         local cmd="$2"
 479
 480         modprobe $DEFAULT_KMOD_DRIVER
 481
 482         local priv=$(eval $cmd)
 483         local unpriv=$(capsh --drop=CAP_SYSLOG -- -c "$cmd")
 484
 485         if [ "$priv" = "$unpriv" ] || \
 486            [ "${priv:0:3}" = "0x0" ] || \
 487            [ "${unpriv:0:3}" != "0x0" ] ; then
 488                 echo "${FUNCNAME[0]}: FAIL, $name visible to unpriv: '$priv' vs '$unpriv'" >&2
 489                 exit 1
 490         else
 491                 echo "${FUNCNAME[0]}: OK!"
 492         fi
 493 }
 494
 495 kmod_test_0012()
 496 {
 497         kmod_check_visibility /proc/modules \
 498                 "grep '^${DEFAULT_KMOD_DRIVER}\b' /proc/modules | awk '{print \$NF}'"
 499 }
 500
 501 kmod_test_0013()
 502 {
 503         kmod_check_visibility '/sys/module/*/sections/*' \
 504                 "cat /sys/module/${DEFAULT_KMOD_DRIVER}/sections/.*text | head -n1"
 505 }
 506
 507 list_tests()
 508 {
 509         echo "Test ID list:"
 510         echo
 511         echo "TEST_ID x NUM_TEST"
 512         echo "TEST_ID:   Test ID"
 513         echo "NUM_TESTS: Number of recommended times to run the test"
 514         echo
 515         echo "0001 x $(get_test_count 0001) - Simple test - 1 thread  for empty string"
 516         echo "0002 x $(get_test_count 0002) - Simple test - 1 thread  for modules/filesystems that do not exist"
 517         echo "0003 x $(get_test_count 0003) - Simple test - 1 thread  for get_fs_type() only"
 518         echo "0004 x $(get_test_count 0004) - Simple test - 2 threads for get_fs_type() only"
 519         echo "0005 x $(get_test_count 0005) - multithreaded tests with default setup - request_module() only"
 520         echo "0006 x $(get_test_count 0006) - multithreaded tests with default setup - get_fs_type() only"
 521         echo "0007 x $(get_test_count 0007) - multithreaded tests with default setup test request_module() and get_fs_type()"
 522         echo "0008 x $(get_test_count 0008) - multithreaded - push kmod_concurrent over max_modprobes for request_module()"
 523         echo "0009 x $(get_test_count 0009) - multithreaded - push kmod_concurrent over max_modprobes for get_fs_type()"
 524         echo "0010 x $(get_test_count 0010) - test nonexistent modprobe path"
 525         echo "0011 x $(get_test_count 0011) - test completely disabling module autoloading"
 526         echo "0012 x $(get_test_count 0012) - test /proc/modules address visibility under CAP_SYSLOG"
 527         echo "0013 x $(get_test_count 0013) - test /sys/module/*/sections/* visibility under CAP_SYSLOG"
 528 }
 529
 530 usage()
 531 {
 532         NUM_TESTS=$(grep -o ' ' <<<"$ALL_TESTS" | grep -c .)
 533         let NUM_TESTS=$NUM_TESTS+1
 534         MAX_TEST=$(printf "%04d\n" $NUM_TESTS)
 535         echo "Usage: $0 [ -t <4-number-digit> ] | [ -w <4-number-digit> ] |"
 536         echo "           [ -s <4-number-digit> ] | [ -c <4-number-digit> <test- count>"
 537         echo "           [ all ] [ -h | --help ] [ -l ]"
 538         echo ""
 539         echo "Valid tests: 0001-$MAX_TEST"
 540         echo ""
 541         echo "    all     Runs all tests (default)"
 542         echo "    -t      Run test ID the number amount of times is recommended"
 543         echo "    -w      Watch test ID run until it runs into an error"
 544         echo "    -s      Run test ID once"
 545         echo "    -c      Run test ID x test-count number of times"
 546         echo "    -l      List all test ID list"
 547         echo " -h|--help  Help"
 548         echo
 549         echo "If an error every occurs execution will immediately terminate."
 550         echo "If you are adding a new test try using -w <test-ID> first to"
 551         echo "make sure the test passes a series of tests."
 552         echo
 553         echo Example uses:
 554         echo
 555         echo "${TEST_NAME}.sh           -- executes all tests"
 556         echo "${TEST_NAME}.sh -t 0008   -- Executes test ID 0008 number of times is recommended"
 557         echo "${TEST_NAME}.sh -w 0008   -- Watch test ID 0008 run until an error occurs"
 558         echo "${TEST_NAME}.sh -s 0008   -- Run test ID 0008 once"
 559         echo "${TEST_NAME}.sh -c 0008 3 -- Run test ID 0008 three times"
 560         echo
 561         list_tests
 562         exit 1
 563 }
 564
 565 function test_num()
 566 {
 567         re='^[0-9]+$'
 568         if ! [[ $1 =~ $re ]]; then
 569                 usage
 570         fi
 571 }
 572
 573 function get_test_data()
 574 {
 575         test_num $1
 576         local field_num=$(echo $1 | sed 's/^0*//')
 577         echo $ALL_TESTS | awk '{print $'$field_num'}'
 578 }
 579
 580 function get_test_count()
 581 {
 582         TEST_DATA=$(get_test_data $1)
 583         LAST_TWO=${TEST_DATA#*:*}
 584         echo ${LAST_TWO%:*}
 585 }
 586
 587 function get_test_enabled()
 588 {
 589         TEST_DATA=$(get_test_data $1)
 590         echo ${TEST_DATA#*:*:}
 591 }
 592
 593 function run_all_tests()
 594 {
 595         for i in $ALL_TESTS ; do
 596                 TEST_ID=${i%:*:*}
 597                 ENABLED=$(get_test_enabled $TEST_ID)
 598                 TEST_COUNT=$(get_test_count $TEST_ID)
 599                 if [[ $ENABLED -eq "1" ]]; then
 600                         test_case $TEST_ID $TEST_COUNT
 601                 fi
 602         done
 603 }
 604
 605 function watch_log()
 606 {
 607         if [ $# -ne 3 ]; then
 608                 clear
 609         fi
 610         date
 611         echo "Running test: $2 - run #$1"
 612 }
 613
 614 function watch_case()
 615 {
 616         i=0
 617         while [ 1 ]; do
 618
 619                 if [ $# -eq 1 ]; then
 620                         test_num $1
 621                         watch_log $i ${TEST_NAME}_test_$1
 622                         ${TEST_NAME}_test_$1
 623                 else
 624                         watch_log $i all
 625                         run_all_tests
 626                 fi
 627                 let i=$i+1
 628         done
 629 }
 630
 631 function test_case()
 632 {
 633         NUM_TESTS=$DEFAULT_NUM_TESTS
 634         if [ $# -eq 2 ]; then
 635                 NUM_TESTS=$2
 636         fi
 637
 638         i=0
 639         while [ $i -lt $NUM_TESTS ]; do
 640                 test_num $1
 641                 watch_log $i ${TEST_NAME}_test_$1 noclear
 642                 RUN_TEST=${TEST_NAME}_test_$1
 643                 $RUN_TEST
 644                 let i=$i+1
 645         done
 646 }
 647
 648 function parse_args()
 649 {
 650         if [ $# -eq 0 ]; then
 651                 run_all_tests
 652         else
 653                 if [[ "$1" = "all" ]]; then
 654                         run_all_tests
 655                 elif [[ "$1" = "-w" ]]; then
 656                         shift
 657                         watch_case $@
 658                 elif [[ "$1" = "-t" ]]; then
 659                         shift
 660                         test_num $1
 661                         test_case $1 $(get_test_count $1)
 662                 elif [[ "$1" = "-c" ]]; then
 663                         shift
 664                         test_num $1
 665                         test_num $2
 666                         test_case $1 $2
 667                 elif [[ "$1" = "-s" ]]; then
 668                         shift
 669                         test_case $1 1
 670                 elif [[ "$1" = "-l" ]]; then
 671                         list_tests
 672                 elif [[ "$1" = "-h" || "$1" = "--help" ]]; then
 673                         usage
 674                 else
 675                         usage
 676                 fi
 677         fi
 678 }
 679
 680 test_reqs
 681 allow_user_defaults
 682 load_req_mod
 683
 684 MODPROBE=$(</proc/sys/kernel/modprobe)
 685 trap "test_finish" EXIT
 686
 687 parse_args $@
 688
 689 exit 0