diff --git a/MAINTAINERS b/MAINTAINERS
index 567343b8ffaa..f1d6d50932cf 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3527,6 +3527,11 @@ S:	Maintained
 F:	mm/memcontrol.c
 F:	mm/swap_cgroup.c
 
+COMPILE TEST FOR HEADER FILES EXPORTED TO USERSPACE
+M:	Mikko Rapeli <mikko.rapeli@iki.fi>
+S:	Maintained
+F:	scripts/headers_compile_test.sh
+
 CORETEMP HARDWARE MONITORING DRIVER
 M:	Fenghua Yu <fenghua.yu@intel.com>
 L:	linux-hwmon@vger.kernel.org
diff --git a/scripts/headers_compile_test.sh b/scripts/headers_compile_test.sh
new file mode 100755
index 000000000000..99de50d32b7b
--- /dev/null
+++ b/scripts/headers_compile_test.sh
@@ -0,0 +1,507 @@
+#!/bin/bash
+
+help() {
+	cat << EOF_HELP
+Userspace compile test for exported kernel headers.
+
+    Copyright (C) 2015 Mikko Rapeli <mikko.rapeli@iki.fi>
+
+    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; version 2
+    of the License.
+
+Execute in root directory of exported kernel headers in Linux kernel source
+tree. Sets up gcc and libc headers without existing kernel headers to
+a temporary environment and tries to compile all exported header files
+from current directory against them. Return value is zero if all tests pass,
+non-zero if something goes wrong during execution or if any file failed
+the compile tests.
+
+Supported arguments:
+
+    -h|--help          print help
+    -k|--keep          don't cleanup temporary header files and directories
+    -lk|--libc-kernel  test for conflicts between kernel and libc headers
+                       when libc headers are included before kernel headers
+    -kl|--kernel-libc  test for conflicts between kernel and libc headers
+                       when kernel headers are included before libc headers
+    -l|--libc          test both -lk and -kl
+    -v|--verbose       print more verbose output
+
+Example in Linux kernel source tree:
+
+    \$ make headers_install
+    \$ cd usr/include
+    \$ $( readlink -f "$0" )
+
+EOF_HELP
+}
+
+# bash due to arithmetics and pipefail
+set -euo pipefail
+
+KEEP=0
+HELP=0
+LIBC_TEST=0
+LIBC_KERNEL_TEST=0
+KERNEL_LIBC_TEST=0
+
+# command line arguments
+for p in "$@"; do
+	case "$p" in
+		-k|--keep)
+			KEEP=1
+		;;
+		-l|--libc)
+			LIBC_TEST=1
+			LIBC_KERNEL_TEST=1
+			KERNEL_LIBC_TEST=1
+		;;
+		-lk|--libc-kernel)
+			LIBC_TEST=1
+			LIBC_KERNEL_TEST=1
+		;;
+		-kl|--kernel-libc)
+			LIBC_TEST=1
+			KERNEL_LIBC_TEST=1
+		;;
+		-h|--help)
+			HELP=1
+		;;
+		-v|--verbose)
+			set -x
+		;;
+		*)
+			help
+			echo "Unknown argument: $p"
+			exit 1
+		;;
+	esac
+done
+
+if [ "$HELP" != "0" ]; then help; exit 0; fi
+
+# sanity test
+if [ ! -d ./linux ]; then
+	echo Sanity check error: ./linux directory not found
+	echo Should be called in usr/include after \'make headers_install\'.
+	echo Returns number of failed files, 0 if none.
+	exit 1
+fi
+
+# Support CC variable for compiler and ccache, and cross compiling.
+# CC is used without quotes to support CC="ccache gcc".
+set +u
+if [ "$CC"foobar == "foobar" ]; then
+	CC=cc
+fi
+
+if [ "$CROSS_COMPILE"foobar != "foobar" ]; then
+	# Using gcc name since some cross compiler tool chains don't provide
+	# the cc symlink. Using eval to expand ~ to $HOME.
+	CC="$( eval echo "$CROSS_COMPILE"gcc )"
+fi
+set -u
+
+# Kernel headers refer to some gcc and libc headers so make them available.
+set +u
+if [ "$ARCH_TRIPLET"foobar == "foobar" ]; then
+	# Taking triplet from gcc/cpp
+	ARCH_TRIPLET="$( $CC -v -x c -E - < /dev/null 2>&1 | \
+			grep Target | sed -e 's/Target: //' )"
+fi
+
+if [ "$LIBC"foobar == "foobar" ]; then
+	# trying to grep libc includes from gcc/cpp defaults
+	_TEMP="$( $CC -v -x c -E - < /dev/null 2>&1 | \
+		sed -n -e '/^#include <...> search starts here:$/,/^End of search list.$/{//!p}' | \
+		sed -e 's/^\ \//\//g' | \
+		grep '/usr/include' )"
+
+	# sanity check and prepare LIBC dirs
+	for d in $_TEMP; do
+		if [ ! -d "$d" ]; then
+			echo "$d not a directory"
+			exit 1
+		fi
+		LIBC="$LIBC $d"
+	done
+fi
+set -u
+
+# Copy libc include files to temp directory for the tests.
+COMPILE_TEST_INC="$( readlink -f \
+		"$( mktemp -d ../headers_compile_test_include.XXXXXX )" )"
+
+# cleanup if keep not set
+if [ "$KEEP" = "0" ]; then
+	trap 'rm -rf "$COMPILE_TEST_INC"' EXIT
+else
+	trap 'printf \
+"Temporary directory not cleaned up! Remove manually:\n${COMPILE_TEST_INC}\n"' \
+		EXIT
+fi
+
+for d in $LIBC; do
+	# check if last part of dir is the arch triplet, cross compile paths
+	# can have it also elsewhere so just the last one counts.
+	if ! ( echo "$d" | egrep "$ARCH_TRIPLET$" > /dev/null ); then
+		# hopefully just main libc dir, e.g. /usr/include,
+		# follow symlinks from e.g. /usr/include/bits
+		cp -aL "$d"/* "$COMPILE_TEST_INC"/
+	elif ( echo "$d" | egrep "$ARCH_TRIPLET$" > /dev/null ); then
+		# hopefully the arch specific dir, e.g. /usr/include/x86_64-linux-gnu
+		cp -ar "$d"/* "$COMPILE_TEST_INC/"
+	else
+		echo "$d unexpected, bailing out"
+		exit 1
+	fi
+done
+
+# A single header with all non-conflicting libc headers to test kernel
+# headers against libc headers for conflicts.
+if [ "$LIBC_TEST" != 0 ]; then
+	# List taken from Debian unstable libc6 version 2.21-9.
+	# Some glibc headers conflict with each other so they
+	# are filtered out. Not perfect but better than nothing.
+        #
+	# $ for f in $( egrep "\.h$" /var/lib/dpkg/info/libc6-dev\:i386.list | sed -e 's|/usr/include/||'| sort | grep -v arpa | grep -v linux-gnu | grep -v rpcsvc | grep -v regexp.h | grep -v rpc | grep -v scsi | grep -v talkd ); do echo "#include <$f>"; done > libc_headers.h
+
+	cat > "$COMPILE_TEST_INC/libc_headers.h" << EOF_LIBC_HEADERS
+#include <aio.h>
+#include <aliases.h>
+#include <alloca.h>
+#include <argp.h>
+#include <argz.h>
+#include <ar.h>
+#include <assert.h>
+#include <byteswap.h>
+#include <complex.h>
+#include <cpio.h>
+#include <crypt.h>
+#include <ctype.h>
+#include <dirent.h>
+#include <dlfcn.h>
+#include <elf.h>
+#include <endian.h>
+#include <envz.h>
+#include <err.h>
+#include <errno.h>
+#include <error.h>
+#include <execinfo.h>
+#include <fcntl.h>
+#include <features.h>
+#include <fenv.h>
+#include <fmtmsg.h>
+#include <fnmatch.h>
+#include <fstab.h>
+#include <fts.h>
+#include <ftw.h>
+#include <_G_config.h>
+#include <gconv.h>
+#include <getopt.h>
+#include <glob.h>
+#include <gnu-versions.h>
+#include <grp.h>
+#include <gshadow.h>
+#include <iconv.h>
+#include <ifaddrs.h>
+#include <inttypes.h>
+#include <langinfo.h>
+#include <lastlog.h>
+#include <libgen.h>
+#include <libintl.h>
+#include <libio.h>
+#include <limits.h>
+#include <link.h>
+#include <locale.h>
+#include <malloc.h>
+#include <math.h>
+#include <mcheck.h>
+#include <memory.h>
+#include <mntent.h>
+#include <monetary.h>
+#include <mqueue.h>
+#include <netash/ash.h>
+#include <netatalk/at.h>
+#include <netax25/ax25.h>
+#include <netdb.h>
+#include <neteconet/ec.h>
+#include <net/ethernet.h>
+#include <net/if_arp.h>
+#include <net/if.h>
+#include <net/if_packet.h>
+#include <net/if_ppp.h>
+#include <net/if_shaper.h>
+#include <net/if_slip.h>
+#include <netinet/ether.h>
+#include <netinet/icmp6.h>
+#include <netinet/if_ether.h>
+#include <netinet/if_fddi.h>
+#include <netinet/if_tr.h>
+#include <netinet/igmp.h>
+#include <netinet/in.h>
+#include <netinet/in_systm.h>
+#include <netinet/ip6.h>
+#include <netinet/ip.h>
+#include <netinet/ip_icmp.h>
+#include <netinet/tcp.h>
+#include <netinet/udp.h>
+#include <netipx/ipx.h>
+#include <netiucv/iucv.h>
+#include <netpacket/packet.h>
+#include <net/ppp-comp.h>
+#include <net/ppp_defs.h>
+#include <netrom/netrom.h>
+#include <netrose/rose.h>
+#include <net/route.h>
+#include <nfs/nfs.h>
+#include <nl_types.h>
+#include <nss.h>
+#include <obstack.h>
+#include <paths.h>
+#include <poll.h>
+#include <printf.h>
+#include <protocols/routed.h>
+#include <protocols/rwhod.h>
+#include <protocols/timed.h>
+#include <pthread.h>
+#include <pty.h>
+#include <pwd.h>
+#include <re_comp.h>
+#include <regex.h>
+#include <resolv.h>
+#include <sched.h>
+#include <search.h>
+#include <semaphore.h>
+#include <setjmp.h>
+#include <sgtty.h>
+#include <shadow.h>
+#include <signal.h>
+#include <spawn.h>
+#include <stab.h>
+#include <stdc-predef.h>
+#include <stdint.h>
+#include <stdio_ext.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include <stropts.h>
+#include <syscall.h>
+#include <sysexits.h>
+#include <syslog.h>
+#include <tar.h>
+#include <termio.h>
+#include <termios.h>
+#include <tgmath.h>
+#include <thread_db.h>
+#include <time.h>
+#include <ttyent.h>
+#include <uchar.h>
+#include <ucontext.h>
+#include <ulimit.h>
+#include <unistd.h>
+#include <ustat.h>
+#include <utime.h>
+#include <utmp.h>
+#include <utmpx.h>
+#include <values.h>
+#include <wait.h>
+#include <wchar.h>
+#include <wctype.h>
+#include <wordexp.h>
+#include <xlocale.h>
+EOF_LIBC_HEADERS
+
+fi # LIBC_TEST
+
+# Simulate libc headers without kernel headers by removing
+# all known kernel header dirs from the copied libc ones.
+# This seems to magically work.
+_KERNEL_DIRS="$( find . -type d | grep -v '^\.$' )"
+( cd "$COMPILE_TEST_INC" && rm -rf $_KERNEL_DIRS )
+
+# GCC headers
+set +u
+if [ "$GCC_INC"foobar == "foobar" ]; then
+	# Take from $CC default system include paths, filter out
+	# /usr/local/include and /usr/include stuff first, then try to match
+	# for gcc.
+	_TEMP="$( $CC -v -x c -E - < /dev/null 2>&1 | \
+		sed -n -e '/^#include <...> search starts here:$/,/^End of search list.$/{//!p}' | \
+		sed -e 's/^\ \//\//g' | \
+		egrep -v '/usr/local/include' | \
+		egrep -v '/usr/include' | \
+		grep gcc | \
+		xargs )"
+
+	# merge and prepare for use with $CC
+	for d in $_TEMP; do
+		# sanity test
+		if [ ! -d "$d" ]; then
+			echo "$d: is not a directory"
+			exit 1
+		fi
+		GCC_INC="$GCC_INC -I $d"
+	done
+fi
+set -u
+
+# sanity check: test that plain libc headers compile
+if [ "$LIBC_TEST" != 0 ]; then
+	echo "Testing that $COMPILE_TEST_INC/libc_headers.h compiles"
+	$CC -Wall -c -nostdinc $GCC_INC -I . \
+		-I "$COMPILE_TEST_INC" \
+		-I "$COMPILE_TEST_INC/$ARCH_TRIPLET" \
+		-o /dev/null \
+		"$COMPILE_TEST_INC/libc_headers.h"
+fi
+
+# Summary counters:
+_FAILED=0
+_PASSED=0
+_LIBC_FAILED=0
+_LIBC_PASSED=0
+_LIBC_BEFORE_KERNEL_FAILED=0
+_LIBC_BEFORE_KERNEL_PASSED=0
+_KERNEL_BEFORE_LIBC_FAILED=0
+_KERNEL_BEFORE_LIBC_PASSED=0
+
+# For each header file, try to compile it using the headers we prepared.
+for f in $( find . -name "*\.h" -printf "%P\n" ); do
+	_FAIL=0
+	_FAIL_LIBC=0
+	_FAIL_LIBC_BEFORE_KERNEL=0
+	_FAIL_KERNEL_BEFORE_LIBC=0
+
+	# compile test, CC not quoted to support ccache
+	echo $CC -Wall -c -nostdinc $GCC_INC -I . -I "$COMPILE_TEST_INC" -I "$COMPILE_TEST_INC/$ARCH_TRIPLET" -o /dev/null "$PWD/$f"
+	$CC -Wall -c -nostdinc $GCC_INC -I . -I "$COMPILE_TEST_INC" -I "$COMPILE_TEST_INC/$ARCH_TRIPLET" -o /dev/null "$PWD/$f" \
+		|| _FAIL=1
+
+	# report errors
+	if [ "$_FAIL" -gt 0 ]; then
+		echo "FAILED: $f"
+		_FAILED="$(( _FAILED + 1 ))"
+	else
+		echo "PASSED: $f"
+		_PASSED="$(( _PASSED + 1))"
+	fi
+
+	# libc header conflict tests
+	if [ "$LIBC_TEST" != 0 ]; then
+		_LIBC_BEFORE_KERNEL="$PWD/$f"_libc_before_kernel.h
+		_KERNEL_BEFORE_LIBC="$PWD/$f"_kernel_before_libc.h
+
+		# libc header included before kernel header
+		if [ "$LIBC_KERNEL_TEST" != 0 ]; then
+			cat > "$_LIBC_BEFORE_KERNEL" << EOF_LIBC_BEFORE_KERNEL
+#include <libc_headers.h>
+#include <$f>
+EOF_LIBC_BEFORE_KERNEL
+			echo \
+				$CC -Wall -c -nostdinc $GCC_INC \
+				-I . -I "$COMPILE_TEST_INC" \
+				-I "$COMPILE_TEST_INC/$ARCH_TRIPLET" \
+				-o /dev/null "$_LIBC_BEFORE_KERNEL"
+			$CC -Wall -c -nostdinc $GCC_INC \
+				-I . -I "$COMPILE_TEST_INC" \
+				-I "$COMPILE_TEST_INC/$ARCH_TRIPLET" \
+				-o /dev/null "$_LIBC_BEFORE_KERNEL" \
+				|| _FAIL_LIBC_BEFORE_KERNEL=1
+
+			# report errors
+			if [ "$_FAIL_LIBC_BEFORE_KERNEL" -gt 0 ]; then
+				echo "FAILED libc before kernel test: $f"
+				_LIBC_BEFORE_KERNEL_FAILED="$(( _LIBC_BEFORE_KERNEL_FAILED + 1 ))"
+			else
+				echo "PASSED libc before kernel test: $f"
+				_LIBC_BEFORE_KERNEL_PASSED="$(( _LIBC_BEFORE_KERNEL_PASSED + 1))"
+			fi
+		fi
+
+		# kernel header included before libc
+		if [ "$KERNEL_LIBC_TEST" != 0 ]; then
+			cat > "$_KERNEL_BEFORE_LIBC" << EOF_KERNEL_BEFORE_LIBC
+#include <$f>
+#include <libc_headers.h>
+EOF_KERNEL_BEFORE_LIBC
+			echo \
+				$CC -Wall -c -nostdinc $GCC_INC \
+				-I . -I "$COMPILE_TEST_INC" \
+				-I "$COMPILE_TEST_INC/$ARCH_TRIPLET" \
+				-o /dev/null "$_KERNEL_BEFORE_LIBC"
+			$CC -Wall -c -nostdinc $GCC_INC \
+				-I . -I "$COMPILE_TEST_INC" \
+				-I "$COMPILE_TEST_INC/$ARCH_TRIPLET" \
+				-o /dev/null "$_KERNEL_BEFORE_LIBC" \
+				|| _FAIL_KERNEL_BEFORE_LIBC=1
+
+			# report errors
+			if [ "$_FAIL_KERNEL_BEFORE_LIBC" -gt 0 ]; then
+				echo "FAILED kernel before libc test: $f"
+				_KERNEL_BEFORE_LIBC_FAILED="$(( _KERNEL_BEFORE_LIBC_FAILED + 1 ))"
+			else
+				echo "PASSED kernel before libc test: $f"
+				_KERNEL_BEFORE_LIBC_PASSED="$(( _KERNEL_BEFORE_LIBC_PASSED + 1))"
+			fi
+		fi
+
+		# libc summary
+		if [ "$_FAIL_LIBC_BEFORE_KERNEL" -gt 0 -o "$_FAIL_KERNEL_BEFORE_LIBC" -gt 0 ]; then
+			_LIBC_FAILED="$(( _LIBC_FAILED + 1))"
+		else
+			_LIBC_PASSED="$(( _LIBC_PASSED + 1))"
+		fi
+
+		if [ "$KEEP" = "0" ]; then
+			rm -f "$_LIBC_BEFORE_KERNEL" "$_KERNEL_BEFORE_LIBC"
+		fi
+	fi # LIBC_TEST
+done
+
+cat << EOF_STATS
+
+Kernel header compile test statistics:
+
+$_FAILED files failed the kernel header compile test.
+$_PASSED files passed the kernel header compile test.
+
+EOF_STATS
+
+if [ "$LIBC_TEST" != 0 ]; then
+	cat << EOF_LIBC_STATS
+libc and kernel header compatibility test statistics:
+EOF_LIBC_STATS
+
+if [ "$LIBC_KERNEL_TEST" != 0 ] && [ "$KERNEL_LIBC_TEST" != 0 ]; then
+	cat << EOF_LIBC_COMBINED
+$_LIBC_FAILED files failed the libc compatibility test.
+$_LIBC_PASSED files passed the libc compatibility test.
+EOF_LIBC_COMBINED
+fi
+
+if [ "$LIBC_KERNEL_TEST" != 0 ]; then
+	cat << EOF_LIBC_KERNEL
+$_LIBC_BEFORE_KERNEL_FAILED files failed libc before kernel include test.
+$_LIBC_BEFORE_KERNEL_PASSED files passed libc before kernel include test.
+EOF_LIBC_KERNEL
+fi
+
+if [ "$KERNEL_LIBC_TEST" != 0 ]; then
+	cat << EOF_KERNEL_LIBC
+$_KERNEL_BEFORE_LIBC_FAILED files failed kernel before libc include test.
+$_KERNEL_BEFORE_LIBC_PASSED files passed kernel before libc include test.
+EOF_KERNEL_LIBC
+fi
+
+fi # LIBC_TEST
+
+# return value, summary of all failures.
+if [ "$(( $_FAILED + $_LIBC_BEFORE_KERNEL_FAILED + $_KERNEL_BEFORE_LIBC_FAILED ))" != 0 ]; then
+	exit 1
+else
+	exit 0
+fi
