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 0000000..fa2ccc5
--- /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 0000000..259f4fd
--- /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 0000000..8cecae9
--- /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