Merge branch 'akpm' (patches from Andrew)

Merge even more updates from Andrew Morton:

 - a few leftovers

 - fault-injector rework

 - add a module loader test driver

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  kmod: throttle kmod thread limit
  kmod: add test driver to stress test the module loader
  MAINTAINERS: give kmod some maintainer love
  xtensa: use generic fb.h
  fault-inject: add /proc/<pid>/fail-nth
  fault-inject: simplify access check for fail-nth
  fault-inject: make fail-nth read/write interface symmetric
  fault-inject: parse as natural 1-based value for fail-nth write interface
  fault-inject: automatically detect the number base for fail-nth write interface
  kernel/watchdog.c: use better pr_fmt prefix
  MAINTAINERS: move the befs tree to kernel.org
  lib/atomic64_test.c: add a test that atomic64_inc_not_zero() returns an int
  mm: fix overflow check in expand_upwards()

3 files changed, 633 insertions, 0 deletions

diff --git a/tools/testing/selftests/kmod/Makefile b/tools/testing/selftests/kmod/Makefile
new file mode 100644
index 000000000000..fa2ccc5fb3de
--- /dev/null
+++ b/tools/testing/selftests/kmod/Makefile
@@ -0,0 +1,11 @@
+# Makefile for kmod loading selftests
+
+# No binaries, but make sure arg-less "make" doesn't trigger "run_tests"
+all:
+
+TEST_PROGS := kmod.sh
+
+include ../lib.mk
+
+# Nothing to clean up.
+clean:
diff --git a/tools/testing/selftests/kmod/config b/tools/testing/selftests/kmod/config
new file mode 100644
index 000000000000..259f4fd6b5e2
--- /dev/null
+++ b/tools/testing/selftests/kmod/config
@@ -0,0 +1,7 @@
+CONFIG_TEST_KMOD=m
+CONFIG_TEST_LKM=m
+CONFIG_XFS_FS=m
+
+# For the module parameter force_init_test is used
+CONFIG_TUN=m
+CONFIG_BTRFS_FS=m
diff --git a/tools/testing/selftests/kmod/kmod.sh b/tools/testing/selftests/kmod/kmod.sh
new file mode 100644
index 000000000000..8cecae9a8bca
--- /dev/null
+++ b/tools/testing/selftests/kmod/kmod.sh
@@ -0,0 +1,615 @@
+#!/bin/bash
+#
+# Copyright (C) 2017 Luis R. Rodriguez <mcgrof@kernel.org>
+#
+# This program is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by the Free
+# Software Foundation; either version 2 of the License, or at your option any
+# later version; or, when distributed separately from the Linux kernel or
+# when incorporated into other software packages, subject to the following
+# license:
+#
+# This program is free software; you can redistribute it and/or modify it
+# under the terms of copyleft-next (version 0.3.1 or later) as published
+# at http://copyleft-next.org/.
+
+# This is a stress test script for kmod, the kernel module loader. It uses
+# test_kmod which exposes a series of knobs for the API for us so we can
+# tweak each test in userspace rather than in kernelspace.
+#
+# The way kmod works is it uses the kernel's usermode helper API to eventually
+# call /sbin/modprobe. It has a limit of the number of concurrent calls
+# possible. The kernel interface to load modules is request_module(), however
+# mount uses get_fs_type(). Both behave slightly differently, but the
+# differences are important enough to test each call separately. For this
+# reason test_kmod starts by providing tests for both calls.
+#
+# The test driver test_kmod assumes a series of defaults which you can
+# override by exporting to your environment prior running this script.
+# For instance this script assumes you do not have xfs loaded upon boot.
+# If this is false, export DEFAULT_KMOD_FS="ext4" prior to running this
+# script if the filesyste module you don't have loaded upon bootup
+# is ext4 instead. Refer to allow_user_defaults() for a list of user
+# override variables possible.
+#
+# You'll want at least 4 GiB of RAM to expect to run these tests
+# without running out of memory on them. For other requirements refer
+# to test_reqs()
+
+set -e
+
+TEST_NAME="kmod"
+TEST_DRIVER="test_${TEST_NAME}"
+TEST_DIR=$(dirname $0)
+
+# This represents
+#
+# TEST_ID:TEST_COUNT:ENABLED
+#
+# TEST_ID: is the test id number
+# TEST_COUNT: number of times we should run the test
+# ENABLED: 1 if enabled, 0 otherwise
+#
+# Once these are enabled please leave them as-is. Write your own test,
+# we have tons of space.
+ALL_TESTS="0001:3:1"
+ALL_TESTS="$ALL_TESTS 0002:3:1"
+ALL_TESTS="$ALL_TESTS 0003:1:1"
+ALL_TESTS="$ALL_TESTS 0004:1:1"
+ALL_TESTS="$ALL_TESTS 0005:10:1"
+ALL_TESTS="$ALL_TESTS 0006:10:1"
+ALL_TESTS="$ALL_TESTS 0007:5:1"
+ALL_TESTS="$ALL_TESTS 0008:150:1"
+ALL_TESTS="$ALL_TESTS 0009:150:1"
+
+test_modprobe()
+{
+       if [ ! -d $DIR ]; then
+               echo "$0: $DIR not present" >&2
+               echo "You must have the following enabled in your kernel:" >&2
+               cat $TEST_DIR/config >&2
+               exit 1
+       fi
+}
+
+function allow_user_defaults()
+{
+        if [ -z $DEFAULT_KMOD_DRIVER ]; then
+                DEFAULT_KMOD_DRIVER="test_module"
+        fi
+
+        if [ -z $DEFAULT_KMOD_FS ]; then
+                DEFAULT_KMOD_FS="xfs"
+        fi
+
+        if [ -z $PROC_DIR ]; then
+                PROC_DIR="/proc/sys/kernel/"
+        fi
+
+        if [ -z $MODPROBE_LIMIT ]; then
+                MODPROBE_LIMIT=50
+        fi
+
+        if [ -z $DIR ]; then
+                DIR="/sys/devices/virtual/misc/${TEST_DRIVER}0/"
+        fi
+
+        if [ -z $DEFAULT_NUM_TESTS ]; then
+                DEFAULT_NUM_TESTS=150
+        fi
+
+        MODPROBE_LIMIT_FILE="${PROC_DIR}/kmod-limit"
+}
+
+test_reqs()
+{
+        if ! which modprobe 2> /dev/null > /dev/null; then
+                echo "$0: You need modprobe installed" >&2
+                exit 1
+        fi
+
+        if ! which kmod 2> /dev/null > /dev/null; then
+                echo "$0: You need kmod installed" >&2
+                exit 1
+        fi
+
+        # kmod 19 has a bad bug where it returns 0 when modprobe
+        # gets called *even* if the module was not loaded due to
+        # some bad heuristics. For details see:
+        #
+        # A work around is possible in-kernel but its rather
+        # complex.
+        KMOD_VERSION=$(kmod --version | awk '{print $3}')
+        if [[ $KMOD_VERSION  -le 19 ]]; then
+                echo "$0: You need at least kmod 20" >&2
+                echo "kmod <= 19 is buggy, for details see:" >&2
+                echo "http://git.kernel.org/cgit/utils/kernel/kmod/kmod.git/commit/libkmod/libkmod-module.c?id=fd44a98ae2eb5eb32161088954ab21e58e19dfc4" >&2
+                exit 1
+        fi
+
+        uid=$(id -u)
+        if [ $uid -ne 0 ]; then
+                echo $msg must be run as root >&2
+                exit 0
+        fi
+}
+
+function load_req_mod()
+{
+        trap "test_modprobe" EXIT
+
+        if [ ! -d $DIR ]; then
+                # Alanis: "Oh isn't it ironic?"
+                modprobe $TEST_DRIVER
+        fi
+}
+
+test_finish()
+{
+        echo "Test completed"
+}
+
+errno_name_to_val()
+{
+        case "$1" in
+        # kmod calls modprobe and upon of a module not found
+        # modprobe returns just 1... However in the kernel we
+        # *sometimes* see 256...
+        MODULE_NOT_FOUND)
+                echo 256;;
+        SUCCESS)
+                echo 0;;
+        -EPERM)
+                echo -1;;
+        -ENOENT)
+                echo -2;;
+        -EINVAL)
+                echo -22;;
+        -ERR_ANY)
+                echo -123456;;
+        *)
+                echo invalid;;
+        esac
+}
+
+errno_val_to_name()
+        case "$1" in
+        256)
+                echo MODULE_NOT_FOUND;;
+        0)
+                echo SUCCESS;;
+        -1)
+                echo -EPERM;;
+        -2)
+                echo -ENOENT;;
+        -22)
+                echo -EINVAL;;
+        -123456)
+                echo -ERR_ANY;;
+        *)
+                echo invalid;;
+        esac
+
+config_set_test_case_driver()
+{
+        if ! echo -n 1 >$DIR/config_test_case; then
+                echo "$0: Unable to set to test case to driver" >&2
+                exit 1
+        fi
+}
+
+config_set_test_case_fs()
+{
+        if ! echo -n 2 >$DIR/config_test_case; then
+                echo "$0: Unable to set to test case to fs" >&2
+                exit 1
+        fi
+}
+
+config_num_threads()
+{
+        if ! echo -n $1 >$DIR/config_num_threads; then
+                echo "$0: Unable to set to number of threads" >&2
+                exit 1
+        fi
+}
+
+config_get_modprobe_limit()
+{
+        if [[ -f ${MODPROBE_LIMIT_FILE} ]] ; then
+                MODPROBE_LIMIT=$(cat $MODPROBE_LIMIT_FILE)
+        fi
+        echo $MODPROBE_LIMIT
+}
+
+config_num_thread_limit_extra()
+{
+        MODPROBE_LIMIT=$(config_get_modprobe_limit)
+        let EXTRA_LIMIT=$MODPROBE_LIMIT+$1
+        config_num_threads $EXTRA_LIMIT
+}
+
+# For special characters use printf directly,
+# refer to kmod_test_0001
+config_set_driver()
+{
+        if ! echo -n $1 >$DIR/config_test_driver; then
+                echo "$0: Unable to set driver" >&2
+                exit 1
+        fi
+}
+
+config_set_fs()
+{
+        if ! echo -n $1 >$DIR/config_test_fs; then
+                echo "$0: Unable to set driver" >&2
+                exit 1
+        fi
+}
+
+config_get_driver()
+{
+        cat $DIR/config_test_driver
+}
+
+config_get_test_result()
+{
+        cat $DIR/test_result
+}
+
+config_reset()
+{
+        if ! echo -n "1" >"$DIR"/reset; then
+                echo "$0: reset shuld have worked" >&2
+                exit 1
+        fi
+}
+
+config_show_config()
+{
+        echo "----------------------------------------------------"
+        cat "$DIR"/config
+        echo "----------------------------------------------------"
+}
+
+config_trigger()
+{
+        if ! echo -n "1" >"$DIR"/trigger_config 2>/dev/null; then
+                echo "$1: FAIL - loading should have worked"
+                config_show_config
+                exit 1
+        fi
+        echo "$1: OK! - loading kmod test"
+}
+
+config_trigger_want_fail()
+{
+        if echo "1" > $DIR/trigger_config 2>/dev/null; then
+                echo "$1: FAIL - test case was expected to fail"
+                config_show_config
+                exit 1
+        fi
+        echo "$1: OK! - kmod test case failed as expected"
+}
+
+config_expect_result()
+{
+        RC=$(config_get_test_result)
+        RC_NAME=$(errno_val_to_name $RC)
+
+        ERRNO_NAME=$2
+        ERRNO=$(errno_name_to_val $ERRNO_NAME)
+
+        if [[ $ERRNO_NAME = "-ERR_ANY" ]]; then
+                if [[ $RC -ge 0 ]]; then
+                        echo "$1: FAIL, test expects $ERRNO_NAME - got $RC_NAME ($RC)" >&2
+                        config_show_config
+                        exit 1
+                fi
+        elif [[ $RC != $ERRNO ]]; then
+                echo "$1: FAIL, test expects $ERRNO_NAME ($ERRNO) - got $RC_NAME ($RC)" >&2
+                config_show_config
+                exit 1
+        fi
+        echo "$1: OK! - Return value: $RC ($RC_NAME), expected $ERRNO_NAME"
+}
+
+kmod_defaults_driver()
+{
+        config_reset
+        modprobe -r $DEFAULT_KMOD_DRIVER
+        config_set_driver $DEFAULT_KMOD_DRIVER
+}
+
+kmod_defaults_fs()
+{
+        config_reset
+        modprobe -r $DEFAULT_KMOD_FS
+        config_set_fs $DEFAULT_KMOD_FS
+        config_set_test_case_fs
+}
+
+kmod_test_0001_driver()
+{
+        NAME='\000'
+
+        kmod_defaults_driver
+        config_num_threads 1
+        printf '\000' >"$DIR"/config_test_driver
+        config_trigger ${FUNCNAME[0]}
+        config_expect_result ${FUNCNAME[0]} MODULE_NOT_FOUND
+}
+
+kmod_test_0001_fs()
+{
+        NAME='\000'
+
+        kmod_defaults_fs
+        config_num_threads 1
+        printf '\000' >"$DIR"/config_test_fs
+        config_trigger ${FUNCNAME[0]}
+        config_expect_result ${FUNCNAME[0]} -EINVAL
+}
+
+kmod_test_0001()
+{
+        kmod_test_0001_driver
+        kmod_test_0001_fs
+}
+
+kmod_test_0002_driver()
+{
+        NAME="nope-$DEFAULT_KMOD_DRIVER"
+
+        kmod_defaults_driver
+        config_set_driver $NAME
+        config_num_threads 1
+        config_trigger ${FUNCNAME[0]}
+        config_expect_result ${FUNCNAME[0]} MODULE_NOT_FOUND
+}
+
+kmod_test_0002_fs()
+{
+        NAME="nope-$DEFAULT_KMOD_FS"
+
+        kmod_defaults_fs
+        config_set_fs $NAME
+        config_trigger ${FUNCNAME[0]}
+        config_expect_result ${FUNCNAME[0]} -EINVAL
+}
+
+kmod_test_0002()
+{
+        kmod_test_0002_driver
+        kmod_test_0002_fs
+}
+
+kmod_test_0003()
+{
+        kmod_defaults_fs
+        config_num_threads 1
+        config_trigger ${FUNCNAME[0]}
+        config_expect_result ${FUNCNAME[0]} SUCCESS
+}
+
+kmod_test_0004()
+{
+        kmod_defaults_fs
+        config_num_threads 2
+        config_trigger ${FUNCNAME[0]}
+        config_expect_result ${FUNCNAME[0]} SUCCESS
+}
+
+kmod_test_0005()
+{
+        kmod_defaults_driver
+        config_trigger ${FUNCNAME[0]}
+        config_expect_result ${FUNCNAME[0]} SUCCESS
+}
+
+kmod_test_0006()
+{
+        kmod_defaults_fs
+        config_trigger ${FUNCNAME[0]}
+        config_expect_result ${FUNCNAME[0]} SUCCESS
+}
+
+kmod_test_0007()
+{
+        kmod_test_0005
+        kmod_test_0006
+}
+
+kmod_test_0008()
+{
+        kmod_defaults_driver
+        MODPROBE_LIMIT=$(config_get_modprobe_limit)
+        let EXTRA=$MODPROBE_LIMIT/6
+        config_num_thread_limit_extra $EXTRA
+        config_trigger ${FUNCNAME[0]}
+        config_expect_result ${FUNCNAME[0]} SUCCESS
+}
+
+kmod_test_0009()
+{
+        kmod_defaults_fs
+        MODPROBE_LIMIT=$(config_get_modprobe_limit)
+        let EXTRA=$MODPROBE_LIMIT/4
+        config_num_thread_limit_extra $EXTRA
+        config_trigger ${FUNCNAME[0]}
+        config_expect_result ${FUNCNAME[0]} SUCCESS
+}
+
+list_tests()
+{
+        echo "Test ID list:"
+        echo
+        echo "TEST_ID x NUM_TEST"
+        echo "TEST_ID:   Test ID"
+        echo "NUM_TESTS: Number of recommended times to run the test"
+        echo
+        echo "0001 x $(get_test_count 0001) - Simple test - 1 thread  for empty string"
+        echo "0002 x $(get_test_count 0002) - Simple test - 1 thread  for modules/filesystems that do not exist"
+        echo "0003 x $(get_test_count 0003) - Simple test - 1 thread  for get_fs_type() only"
+        echo "0004 x $(get_test_count 0004) - Simple test - 2 threads for get_fs_type() only"
+        echo "0005 x $(get_test_count 0005) - multithreaded tests with default setup - request_module() only"
+        echo "0006 x $(get_test_count 0006) - multithreaded tests with default setup - get_fs_type() only"
+        echo "0007 x $(get_test_count 0007) - multithreaded tests with default setup test request_module() and get_fs_type()"
+        echo "0008 x $(get_test_count 0008) - multithreaded - push kmod_concurrent over max_modprobes for request_module()"
+        echo "0009 x $(get_test_count 0009) - multithreaded - push kmod_concurrent over max_modprobes for get_fs_type()"
+}
+
+usage()
+{
+        NUM_TESTS=$(grep -o ' ' <<<"$ALL_TESTS" | grep -c .)
+        let NUM_TESTS=$NUM_TESTS+1
+        MAX_TEST=$(printf "%04d\n" $NUM_TESTS)
+        echo "Usage: $0 [ -t <4-number-digit> ] | [ -w <4-number-digit> ] |"
+        echo "           [ -s <4-number-digit> ] | [ -c <4-number-digit> <test- count>"
+        echo "           [ all ] [ -h | --help ] [ -l ]"
+        echo ""
+        echo "Valid tests: 0001-$MAX_TEST"
+        echo ""
+        echo "    all     Runs all tests (default)"
+        echo "    -t      Run test ID the number amount of times is recommended"
+        echo "    -w      Watch test ID run until it runs into an error"
+        echo "    -c      Run test ID once"
+        echo "    -s      Run test ID x test-count number of times"
+        echo "    -l      List all test ID list"
+        echo " -h|--help  Help"
+        echo
+        echo "If an error every occurs execution will immediately terminate."
+        echo "If you are adding a new test try using -w <test-ID> first to"
+        echo "make sure the test passes a series of tests."
+        echo
+        echo Example uses:
+        echo
+        echo "${TEST_NAME}.sh           -- executes all tests"
+        echo "${TEST_NAME}.sh -t 0008   -- Executes test ID 0008 number of times is recomended"
+        echo "${TEST_NAME}.sh -w 0008   -- Watch test ID 0008 run until an error occurs"
+        echo "${TEST_NAME}.sh -s 0008   -- Run test ID 0008 once"
+        echo "${TEST_NAME}.sh -c 0008 3 -- Run test ID 0008 three times"
+        echo
+        list_tests
+        exit 1
+}
+
+function test_num()
+{
+        re='^[0-9]+$'
+        if ! [[ $1 =~ $re ]]; then
+                usage
+        fi
+}
+
+function get_test_count()
+{
+        test_num $1
+        TEST_DATA=$(echo $ALL_TESTS | awk '{print $'$1'}')
+        LAST_TWO=${TEST_DATA#*:*}
+        echo ${LAST_TWO%:*}
+}
+
+function get_test_enabled()
+{
+        test_num $1
+        TEST_DATA=$(echo $ALL_TESTS | awk '{print $'$1'}')
+        echo ${TEST_DATA#*:*:}
+}
+
+function run_all_tests()
+{
+        for i in $ALL_TESTS ; do
+                TEST_ID=${i%:*:*}
+                ENABLED=$(get_test_enabled $TEST_ID)
+                TEST_COUNT=$(get_test_count $TEST_ID)
+                if [[ $ENABLED -eq "1" ]]; then
+                        test_case $TEST_ID $TEST_COUNT
+                fi
+        done
+}
+
+function watch_log()
+{
+        if [ $# -ne 3 ]; then
+                clear
+        fi
+        date
+        echo "Running test: $2 - run #$1"
+}
+
+function watch_case()
+{
+        i=0
+        while [ 1 ]; do
+
+                if [ $# -eq 1 ]; then
+                        test_num $1
+                        watch_log $i ${TEST_NAME}_test_$1
+                        ${TEST_NAME}_test_$1
+                else
+                        watch_log $i all
+                        run_all_tests
+                fi
+                let i=$i+1
+        done
+}
+
+function test_case()
+{
+        NUM_TESTS=$DEFAULT_NUM_TESTS
+        if [ $# -eq 2 ]; then
+                NUM_TESTS=$2
+        fi
+
+        i=0
+        while [ $i -lt $NUM_TESTS ]; do
+                test_num $1
+                watch_log $i ${TEST_NAME}_test_$1 noclear
+                RUN_TEST=${TEST_NAME}_test_$1
+                $RUN_TEST
+                let i=$i+1
+        done
+}
+
+function parse_args()
+{
+        if [ $# -eq 0 ]; then
+                run_all_tests
+        else
+                if [[ "$1" = "all" ]]; then
+                        run_all_tests
+                elif [[ "$1" = "-w" ]]; then
+                        shift
+                        watch_case $@
+                elif [[ "$1" = "-t" ]]; then
+                        shift
+                        test_num $1
+                        test_case $1 $(get_test_count $1)
+                elif [[ "$1" = "-c" ]]; then
+                        shift
+                        test_num $1
+                        test_num $2
+                        test_case $1 $2
+                elif [[ "$1" = "-s" ]]; then
+                        shift
+                        test_case $1 1
+                elif [[ "$1" = "-l" ]]; then
+                        list_tests
+                elif [[ "$1" = "-h" || "$1" = "--help" ]]; then
+                        usage
+                else
+                        usage
+                fi
+        fi
+}
+
+test_reqs
+allow_user_defaults
+load_req_mod
+
+trap "test_finish" EXIT
+
+parse_args $@
+
+exit 0