These changes are the raw update to linux-4.4.6-rt14. Kernel sources

are taken from kernel.org, and rt patch from the rt wiki download page.

During the rebasing, the following patch collided:

Force tick interrupt and get rid of softirq magic(I70131fb85).

Collisions have been removed because its logic was found on the
source already.

Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769
Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>

21 files changed, 427 insertions, 36 deletions

diff --git a/kernel/tools/build/.gitignore b/kernel/tools/build/.gitignore
new file mode 100644
index 000000000..a776371a3
--- /dev/null
+++ b/kernel/tools/build/.gitignore
@@ -0,0 +1 @@
+fixdep
diff --git a/kernel/tools/build/Build b/kernel/tools/build/Build
new file mode 100644
index 000000000..63a6c34c0
--- /dev/null
+++ b/kernel/tools/build/Build
@@ -0,0 +1 @@
+fixdep-y := fixdep.o
diff --git a/kernel/tools/build/Build.include b/kernel/tools/build/Build.include
index 4c8daaccb..4d000bc95 100644
--- a/kernel/tools/build/Build.include
+++ b/kernel/tools/build/Build.include
@@ -55,14 +55,25 @@ make-cmd = $(call escsq,$(subst \#,\\\#,$(subst $$,$$$$,$(cmd_$(1)))))
 any-prereq = $(filter-out $(PHONY),$?) $(filter-out $(PHONY) $(wildcard $^),$^)
 
 ###
+# Copy dependency data into .cmd file
+#  - gcc -M dependency info
+#  - command line to create object 'cmd_object :='
+dep-cmd = $(if $(wildcard $(fixdep)),                                           \
+           $(fixdep) $(depfile) $@ '$(make-cmd)' > $(dot-target).tmp;           \
+           rm -f $(depfile);                                                    \
+           mv -f $(dot-target).tmp $(dot-target).cmd,                           \
+           printf '\# cannot find fixdep (%s)\n' $(fixdep) > $(dot-target).cmd; \
+           printf '\# using basic dep data\n\n' >> $(dot-target).cmd;           \
+           cat $(depfile) >> $(dot-target).cmd;                                 \
+           printf '%s\n' 'cmd_$@ := $(make-cmd)' >> $(dot-target).cmd)
+
+###
 # if_changed_dep  - execute command if any prerequisite is newer than
 #                   target, or command line has changed and update
 #                   dependencies in the cmd file
 if_changed_dep = $(if $(strip $(any-prereq) $(arg-check)),         \
 	@set -e;                                                   \
-	$(echo-cmd) $(cmd_$(1));                                   \
-	cat $(depfile) > $(dot-target).cmd;                        \
-	printf '%s\n' 'cmd_$@ := $(make-cmd)' >> $(dot-target).cmd)
+	$(echo-cmd) $(cmd_$(1)) && $(dep-cmd))
 
 # if_changed      - execute command if any prerequisite is newer than
 #                   target, or command line has changed
diff --git a/kernel/tools/build/Documentation/Build.txt b/kernel/tools/build/Documentation/Build.txt
index 00ad2d608..a47bffbae 100644
--- a/kernel/tools/build/Documentation/Build.txt
+++ b/kernel/tools/build/Documentation/Build.txt
@@ -11,8 +11,9 @@ Unlike the kernel we don't have a single build object 'obj-y' list that where
 we setup source objects, but we support more. This allows one 'Build' file to
 carry a sources list for multiple build objects.
 
-a) Build framework makefiles
-----------------------------
+
+Build framework makefiles
+-------------------------
 
 The build framework consists of 2 Makefiles:
 
@@ -23,7 +24,7 @@ While the 'Build.include' file contains just some generic definitions, the
 'Makefile.build' file is the makefile used from the outside. It's
 interface/usage is following:
 
-  $ make -f tools/build/Makefile srctree=$(KSRC) dir=$(DIR) obj=$(OBJECT)
+  $ make -f tools/build/Makefile.build srctree=$(KSRC) dir=$(DIR) obj=$(OBJECT)
 
 where:
 
@@ -38,8 +39,9 @@ called $(OBJECT)-in.o:
 
 which includes all compiled sources described in 'Build' makefiles.
 
-a) Build makefiles
-------------------
+
+Build makefiles
+---------------
 
 The user supplies 'Build' makefiles that contains a objects list, and connects
 the build to nested directories.
@@ -66,6 +68,7 @@ To follow the above example, the user provides following 'Build' files:
   ex/Build:
     ex-y += a.o
     ex-y += b.o
+    ex-y += b.o # duplicates in the lists are allowed
 
     libex-y += c.o
     libex-y += d.o
@@ -94,8 +97,31 @@ It's only a matter of 2 single commands to create the final binaries:
 
 You can check the 'ex' example in 'tools/build/tests/ex' for more details.
 
-b) Rules
---------
+
+Makefile.include
+----------------
+
+The tools/build/Makefile.include makefile could be included
+via user makefiles to get usefull definitions.
+
+It defines following interface:
+
+  - build macro definition:
+      build := -f $(srctree)/tools/build/Makefile.build dir=. obj
+
+    to make it easier to invoke build like:
+      make $(build)=ex
+
+
+Fixdep
+------
+It is necessary to build the fixdep helper before invoking the build.
+The Makefile.include file adds the fixdep target, that could be
+invoked by the user.
+
+
+Rules
+-----
 
 The build framework provides standard compilation rules to handle .S and .c
 compilation.
@@ -103,8 +129,9 @@ compilation.
 It's possible to include special rule if needed (like we do for flex or bison
 code generation).
 
-c) CFLAGS
----------
+
+CFLAGS
+------
 
 It's possible to alter the standard object C flags in the following way:
 
@@ -114,8 +141,8 @@ It's possible to alter the standard object C flags in the following way:
 This C flags changes has the scope of the Build makefile they are defined in.
 
 
-d) Dependencies
----------------
+Dependencies
+------------
 
 For each built object file 'a.o' the '.a.cmd' is created and holds:
 
@@ -129,8 +156,8 @@ All existing '.cmd' files are included in the Build process to follow properly
 the dependencies and trigger a rebuild when necessary.
 
 
-e) Single rules
----------------
+Single rules
+------------
 
 It's possible to build single object file by choice, like:
 
diff --git a/kernel/tools/build/Makefile b/kernel/tools/build/Makefile
new file mode 100644
index 000000000..a93036272
--- /dev/null
+++ b/kernel/tools/build/Makefile
@@ -0,0 +1,43 @@
+ifeq ($(srctree),)
+srctree := $(patsubst %/,%,$(dir $(shell pwd)))
+srctree := $(patsubst %/,%,$(dir $(srctree)))
+endif
+
+include $(srctree)/tools//scripts/Makefile.include
+
+define allow-override
+  $(if $(or $(findstring environment,$(origin $(1))),\
+            $(findstring command line,$(origin $(1)))),,\
+    $(eval $(1) = $(2)))
+endef
+
+$(call allow-override,CC,$(CROSS_COMPILE)gcc)
+$(call allow-override,LD,$(CROSS_COMPILE)ld)
+
+ifeq ($(V),1)
+  Q =
+else
+  Q = @
+endif
+
+export Q srctree CC LD
+
+MAKEFLAGS := --no-print-directory
+build     := -f $(srctree)/tools/build/Makefile.build dir=. obj
+
+all: fixdep
+
+clean:
+	$(call QUIET_CLEAN, fixdep)
+	$(Q)find . -name '*.o' -delete -o -name '\.*.cmd' -delete -o -name '\.*.d' -delete
+	$(Q)rm -f fixdep
+
+$(OUTPUT)fixdep-in.o: FORCE
+	$(Q)$(MAKE) $(build)=fixdep
+
+$(OUTPUT)fixdep: $(OUTPUT)fixdep-in.o
+	$(QUIET_LINK)$(CC) $(LDFLAGS) -o $@ $<
+
+FORCE:
+
+.PHONY: FORCE
diff --git a/kernel/tools/build/Makefile.build b/kernel/tools/build/Makefile.build
index 98cfc388e..4a96473b1 100644
--- a/kernel/tools/build/Makefile.build
+++ b/kernel/tools/build/Makefile.build
@@ -21,11 +21,18 @@ endif
 
 build-dir := $(srctree)/tools/build
 
+# Define $(fixdep) for dep-cmd function
+ifeq ($(OUTPUT),)
+  fixdep := $(build-dir)/fixdep
+else
+  fixdep := $(OUTPUT)/fixdep
+endif
+
 # Generic definitions
 include $(build-dir)/Build.include
 
 # do not force detected configuration
--include .config-detected
+-include $(OUTPUT).config-detected
 
 # Init all relevant variables used in build files so
 # 1) they have correct type
@@ -37,7 +44,7 @@ subdir-obj-y :=
 
 # Build definitions
 build-file := $(dir)/Build
-include $(build-file)
+-include $(build-file)
 
 quiet_cmd_flex  = FLEX     $@
 quiet_cmd_bison = BISON    $@
@@ -57,11 +64,13 @@ quiet_cmd_cc_i_c = CPP      $@
 quiet_cmd_cc_s_c = AS       $@
       cmd_cc_s_c = $(CC) $(c_flags) -S -o $@ $<
 
+quiet_cmd_gen = GEN      $@
+
 # Link agregate command
 # If there's nothing to link, create empty $@ object.
 quiet_cmd_ld_multi = LD       $@
       cmd_ld_multi = $(if $(strip $(obj-y)),\
-		       $(LD) -r -o $@ $(obj-y),rm -f $@; $(AR) rcs $@)
+		       $(LD) -r -o $@  $(filter $(obj-y),$^),rm -f $@; $(AR) rcs $@)
 
 # Build rules
 $(OUTPUT)%.o: %.c FORCE
diff --git a/kernel/tools/build/Makefile.feature b/kernel/tools/build/Makefile.feature
index 3a0b0ca2a..37ff4c9f9 100644
--- a/kernel/tools/build/Makefile.feature
+++ b/kernel/tools/build/Makefile.feature
@@ -27,7 +27,7 @@ endef
 #   the rule that uses them - an example for that is the 'bionic'
 #   feature check. ]
 #
-FEATURE_TESTS =			\
+FEATURE_TESTS ?=			\
 	backtrace			\
 	dwarf				\
 	fortify-source			\
@@ -41,6 +41,7 @@ FEATURE_TESTS =			\
 	libelf-getphdrnum		\
 	libelf-mmap			\
 	libnuma				\
+	numa_num_possible_cpus		\
 	libperl				\
 	libpython			\
 	libpython-version		\
@@ -51,9 +52,11 @@ FEATURE_TESTS =			\
 	timerfd				\
 	libdw-dwarf-unwind		\
 	zlib				\
-	lzma
+	lzma				\
+	get_cpuid			\
+	bpf
 
-FEATURE_DISPLAY =			\
+FEATURE_DISPLAY ?=			\
 	dwarf				\
 	glibc				\
 	gtk2				\
@@ -61,13 +64,16 @@ FEATURE_DISPLAY =			\
 	libbfd				\
 	libelf				\
 	libnuma				\
+	numa_num_possible_cpus		\
 	libperl				\
 	libpython			\
 	libslang			\
 	libunwind			\
 	libdw-dwarf-unwind		\
 	zlib				\
-	lzma
+	lzma				\
+	get_cpuid			\
+	bpf
 
 # Set FEATURE_CHECK_(C|LD)FLAGS-all for all FEATURE_TESTS features.
 # If in the future we need per-feature checks/flags for features not
@@ -117,8 +123,9 @@ define feature_print_text_code
     MSG = $(shell printf '...%30s: %s' $(1) $(2))
 endef
 
+FEATURE_DUMP_FILENAME = $(OUTPUT)FEATURE-DUMP$(FEATURE_USER)
 FEATURE_DUMP := $(foreach feat,$(FEATURE_DISPLAY),feature-$(feat)($(feature-$(feat))))
-FEATURE_DUMP_FILE := $(shell touch $(OUTPUT)FEATURE-DUMP; cat $(OUTPUT)FEATURE-DUMP)
+FEATURE_DUMP_FILE := $(shell touch $(FEATURE_DUMP_FILENAME); cat $(FEATURE_DUMP_FILENAME))
 
 ifeq ($(dwarf-post-unwind),1)
   FEATURE_DUMP += dwarf-post-unwind($(dwarf-post-unwind-text))
@@ -127,16 +134,16 @@ endif
 # The $(feature_display) controls the default detection message
 # output. It's set if:
 # - detected features differes from stored features from
-#   last build (in FEATURE-DUMP file)
+#   last build (in $(FEATURE_DUMP_FILENAME) file)
 # - one of the $(FEATURE_DISPLAY) is not detected
 # - VF is enabled
 
 ifneq ("$(FEATURE_DUMP)","$(FEATURE_DUMP_FILE)")
-  $(shell echo "$(FEATURE_DUMP)" > $(OUTPUT)FEATURE-DUMP)
+  $(shell echo "$(FEATURE_DUMP)" > $(FEATURE_DUMP_FILENAME))
   feature_display := 1
 endif
 
-feature_display_check = $(eval $(feature_check_code))
+feature_display_check = $(eval $(feature_check_display_code))
 define feature_display_check_code
   ifneq ($(feature-$(1)), 1)
     feature_display := 1
diff --git a/kernel/tools/build/Makefile.include b/kernel/tools/build/Makefile.include
new file mode 100644
index 000000000..4e09ad617
--- /dev/null
+++ b/kernel/tools/build/Makefile.include
@@ -0,0 +1,10 @@
+build := -f $(srctree)/tools/build/Makefile.build dir=. obj
+
+ifdef CROSS_COMPILE
+fixdep:
+else
+fixdep:
+	$(Q)$(MAKE) -C $(srctree)/tools/build fixdep
+endif
+
+.PHONY: fixdep
diff --git a/kernel/tools/build/feature/Makefile b/kernel/tools/build/feature/Makefile
index 463ed8f2a..cea04ce9f 100644
--- a/kernel/tools/build/feature/Makefile
+++ b/kernel/tools/build/feature/Makefile
@@ -19,6 +19,7 @@ FILES=					\
 	test-libelf-getphdrnum.bin	\
 	test-libelf-mmap.bin		\
 	test-libnuma.bin		\
+	test-numa_num_possible_cpus.bin	\
 	test-libperl.bin		\
 	test-libpython.bin		\
 	test-libpython-version.bin	\
@@ -33,7 +34,9 @@ FILES=					\
 	test-compile-32.bin		\
 	test-compile-x32.bin		\
 	test-zlib.bin			\
-	test-lzma.bin
+	test-lzma.bin			\
+	test-bpf.bin			\
+	test-get_cpuid.bin
 
 CC := $(CROSS_COMPILE)gcc -MD
 PKG_CONFIG := $(CROSS_COMPILE)pkg-config
@@ -69,8 +72,13 @@ test-libelf.bin:
 test-glibc.bin:
 	$(BUILD)
 
+DWARFLIBS := -ldw
+ifeq ($(findstring -static,${LDFLAGS}),-static)
+DWARFLIBS += -lelf -lebl -lz -llzma -lbz2
+endif
+
 test-dwarf.bin:
-	$(BUILD) -ldw
+	$(BUILD) $(DWARFLIBS)
 
 test-libelf-mmap.bin:
 	$(BUILD) -lelf
@@ -81,6 +89,9 @@ test-libelf-getphdrnum.bin:
 test-libnuma.bin:
 	$(BUILD) -lnuma
 
+test-numa_num_possible_cpus.bin:
+	$(BUILD) -lnuma
+
 test-libunwind.bin:
 	$(BUILD) -lelf
 
@@ -121,10 +132,10 @@ test-libbfd.bin:
 	$(BUILD) -DPACKAGE='"perf"' -lbfd -lz -liberty -ldl
 
 test-liberty.bin:
-	$(CC) -Wall -Werror -o $(OUTPUT)$@ test-libbfd.c -DPACKAGE='"perf"' -lbfd -ldl -liberty
+	$(CC) $(CFLAGS) -Wall -Werror -o $(OUTPUT)$@ test-libbfd.c -DPACKAGE='"perf"' $(LDFLAGS) -lbfd -ldl -liberty
 
 test-liberty-z.bin:
-	$(CC) -Wall -Werror -o $(OUTPUT)$@ test-libbfd.c -DPACKAGE='"perf"' -lbfd -ldl -liberty -lz
+	$(CC) $(CFLAGS) -Wall -Werror -o $(OUTPUT)$@ test-libbfd.c -DPACKAGE='"perf"' $(LDFLAGS) -lbfd -ldl -liberty -lz
 
 test-cplus-demangle.bin:
 	$(BUILD) -liberty
@@ -156,6 +167,12 @@ test-zlib.bin:
 test-lzma.bin:
 	$(BUILD) -llzma
 
+test-get_cpuid.bin:
+	$(BUILD)
+
+test-bpf.bin:
+	$(BUILD)
+
 -include *.d
 
 ###############################
diff --git a/kernel/tools/build/feature/test-all.c b/kernel/tools/build/feature/test-all.c
index 84689a678..33cf6f20b 100644
--- a/kernel/tools/build/feature/test-all.c
+++ b/kernel/tools/build/feature/test-all.c
@@ -77,6 +77,10 @@
 # include "test-libnuma.c"
 #undef main
 
+#define main main_test_numa_num_possible_cpus
+# include "test-numa_num_possible_cpus.c"
+#undef main
+
 #define main main_test_timerfd
 # include "test-timerfd.c"
 #undef main
@@ -117,6 +121,10 @@
 # include "test-lzma.c"
 #undef main
 
+#define main main_test_get_cpuid
+# include "test-get_cpuid.c"
+#undef main
+
 int main(int argc, char *argv[])
 {
 	main_test_libpython();
@@ -136,6 +144,7 @@ int main(int argc, char *argv[])
 	main_test_libbfd();
 	main_test_backtrace();
 	main_test_libnuma();
+	main_test_numa_num_possible_cpus();
 	main_test_timerfd();
 	main_test_stackprotector_all();
 	main_test_libdw_dwarf_unwind();
@@ -143,6 +152,7 @@ int main(int argc, char *argv[])
 	main_test_zlib();
 	main_test_pthread_attr_setaffinity_np();
 	main_test_lzma();
+	main_test_get_cpuid();
 
 	return 0;
 }
diff --git a/kernel/tools/build/feature/test-bpf.c b/kernel/tools/build/feature/test-bpf.c
new file mode 100644
index 000000000..062bac811
--- /dev/null
+++ b/kernel/tools/build/feature/test-bpf.c
@@ -0,0 +1,18 @@
+#include <linux/bpf.h>
+
+int main(void)
+{
+	union bpf_attr attr;
+
+	attr.prog_type = BPF_PROG_TYPE_KPROBE;
+	attr.insn_cnt = 0;
+	attr.insns = 0;
+	attr.license = 0;
+	attr.log_buf = 0;
+	attr.log_size = 0;
+	attr.log_level = 0;
+	attr.kern_version = 0;
+
+	attr = attr;
+	return 0;
+}
diff --git a/kernel/tools/build/feature/test-get_cpuid.c b/kernel/tools/build/feature/test-get_cpuid.c
new file mode 100644
index 000000000..d7a2c4071
--- /dev/null
+++ b/kernel/tools/build/feature/test-get_cpuid.c
@@ -0,0 +1,7 @@
+#include <cpuid.h>
+
+int main(void)
+{
+	unsigned int eax = 0, ebx = 0, ecx = 0, edx = 0;
+	return __get_cpuid(0x15, &eax, &ebx, &ecx, &edx);
+}
diff --git a/kernel/tools/build/feature/test-glibc.c b/kernel/tools/build/feature/test-glibc.c
index b0820345c..9367f7586 100644
--- a/kernel/tools/build/feature/test-glibc.c
+++ b/kernel/tools/build/feature/test-glibc.c
@@ -1,8 +1,19 @@
+#include <stdlib.h>
+
+#if !defined(__UCLIBC__)
 #include <gnu/libc-version.h>
+#else
+#define XSTR(s) STR(s)
+#define STR(s) #s
+#endif
 
 int main(void)
 {
+#if !defined(__UCLIBC__)
 	const char *version = gnu_get_libc_version();
+#else
+	const char *version = XSTR(__GLIBC__) "." XSTR(__GLIBC_MINOR__);
+#endif
 
 	return (long)version;
 }
diff --git a/kernel/tools/build/feature/test-numa_num_possible_cpus.c b/kernel/tools/build/feature/test-numa_num_possible_cpus.c
new file mode 100644
index 000000000..2606e94b0
--- /dev/null
+++ b/kernel/tools/build/feature/test-numa_num_possible_cpus.c
@@ -0,0 +1,6 @@
+#include <numa.h>
+
+int main(void)
+{
+	return numa_num_possible_cpus();
+}
diff --git a/kernel/tools/build/fixdep.c b/kernel/tools/build/fixdep.c
new file mode 100644
index 000000000..1521d36ce
--- /dev/null
+++ b/kernel/tools/build/fixdep.c
@@ -0,0 +1,168 @@
+/*
+ * "Optimize" a list of dependencies as spit out by gcc -MD
+ * for the build framework.
+ *
+ * Original author:
+ *   Copyright    2002 by Kai Germaschewski  <kai.germaschewski@gmx.de>
+ *
+ * This code has been borrowed from kbuild's fixdep (scripts/basic/fixdep.c),
+ * Please check it for detailed explanation. This fixdep borow only the
+ * base transformation of dependecies without the CONFIG mangle.
+ */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <limits.h>
+
+char *target;
+char *depfile;
+char *cmdline;
+
+static void usage(void)
+{
+	fprintf(stderr, "Usage: fixdep <depfile> <target> <cmdline>\n");
+	exit(1);
+}
+
+/*
+ * Print out the commandline prefixed with cmd_<target filename> :=
+ */
+static void print_cmdline(void)
+{
+	printf("cmd_%s := %s\n\n", target, cmdline);
+}
+
+/*
+ * Important: The below generated source_foo.o and deps_foo.o variable
+ * assignments are parsed not only by make, but also by the rather simple
+ * parser in scripts/mod/sumversion.c.
+ */
+static void parse_dep_file(void *map, size_t len)
+{
+	char *m = map;
+	char *end = m + len;
+	char *p;
+	char s[PATH_MAX];
+	int is_target;
+	int saw_any_target = 0;
+	int is_first_dep = 0;
+
+	while (m < end) {
+		/* Skip any "white space" */
+		while (m < end && (*m == ' ' || *m == '\\' || *m == '\n'))
+			m++;
+		/* Find next "white space" */
+		p = m;
+		while (p < end && *p != ' ' && *p != '\\' && *p != '\n')
+			p++;
+		/* Is the token we found a target name? */
+		is_target = (*(p-1) == ':');
+		/* Don't write any target names into the dependency file */
+		if (is_target) {
+			/* The /next/ file is the first dependency */
+			is_first_dep = 1;
+		} else {
+			/* Save this token/filename */
+			memcpy(s, m, p-m);
+			s[p - m] = 0;
+
+			/*
+			 * Do not list the source file as dependency,
+			 * so that kbuild is not confused if a .c file
+			 * is rewritten into .S or vice versa. Storing
+			 * it in source_* is needed for modpost to
+			 * compute srcversions.
+			 */
+			if (is_first_dep) {
+				/*
+				 * If processing the concatenation of
+				 * multiple dependency files, only
+				 * process the first target name, which
+				 * will be the original source name,
+				 * and ignore any other target names,
+				 * which will be intermediate temporary
+				 * files.
+				 */
+				if (!saw_any_target) {
+					saw_any_target = 1;
+					printf("source_%s := %s\n\n",
+						target, s);
+					printf("deps_%s := \\\n",
+						target);
+				}
+				is_first_dep = 0;
+			} else
+				printf("  %s \\\n", s);
+		}
+		/*
+		 * Start searching for next token immediately after the first
+		 * "whitespace" character that follows this token.
+		 */
+		m = p + 1;
+	}
+
+	if (!saw_any_target) {
+		fprintf(stderr, "fixdep: parse error; no targets found\n");
+		exit(1);
+	}
+
+	printf("\n%s: $(deps_%s)\n\n", target, target);
+	printf("$(deps_%s):\n", target);
+}
+
+static void print_deps(void)
+{
+	struct stat st;
+	int fd;
+	void *map;
+
+	fd = open(depfile, O_RDONLY);
+	if (fd < 0) {
+		fprintf(stderr, "fixdep: error opening depfile: ");
+		perror(depfile);
+		exit(2);
+	}
+	if (fstat(fd, &st) < 0) {
+		fprintf(stderr, "fixdep: error fstat'ing depfile: ");
+		perror(depfile);
+		exit(2);
+	}
+	if (st.st_size == 0) {
+		fprintf(stderr, "fixdep: %s is empty\n", depfile);
+		close(fd);
+		return;
+	}
+	map = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
+	if ((long) map == -1) {
+		perror("fixdep: mmap");
+		close(fd);
+		return;
+	}
+
+	parse_dep_file(map, st.st_size);
+
+	munmap(map, st.st_size);
+
+	close(fd);
+}
+
+int main(int argc, char **argv)
+{
+	if (argc != 4)
+		usage();
+
+	depfile = argv[1];
+	target  = argv[2];
+	cmdline = argv[3];
+
+	print_cmdline();
+	print_deps();
+
+	return 0;
+}
diff --git a/kernel/tools/build/tests/ex/Build b/kernel/tools/build/tests/ex/Build
index 0e6c3e676..4d502f9b1 100644
--- a/kernel/tools/build/tests/ex/Build
+++ b/kernel/tools/build/tests/ex/Build
@@ -1,7 +1,10 @@
 ex-y += ex.o
 ex-y += a.o
 ex-y += b.o
+ex-y += b.o
 ex-y += empty/
+ex-y += empty2/
+ex-y += inc.o
 
 libex-y += c.o
 libex-y += d.o
diff --git a/kernel/tools/build/tests/ex/Makefile b/kernel/tools/build/tests/ex/Makefile
index 52d247607..c50d5782a 100644
--- a/kernel/tools/build/tests/ex/Makefile
+++ b/kernel/tools/build/tests/ex/Makefile
@@ -1,19 +1,22 @@
-export srctree := ../../../..
+export srctree := $(abspath ../../../..)
 export CC      := gcc
 export LD      := ld
 export AR      := ar
 
-build := -f $(srctree)/tools/build/Makefile.build dir=. obj
+ex:
+
+include $(srctree)/tools/build/Makefile.include
+
 ex: ex-in.o libex-in.o
 	gcc -o $@ $^
 
-ex.%: FORCE
+ex.%: fixdep FORCE
 	make -f $(srctree)/tools/build/Makefile.build dir=. $@
 
-ex-in.o: FORCE
+ex-in.o: fixdep FORCE
 	make $(build)=ex
 
-libex-in.o: FORCE
+libex-in.o: fixdep FORCE
 	make $(build)=libex
 
 clean:
diff --git a/kernel/tools/build/tests/ex/empty2/README b/kernel/tools/build/tests/ex/empty2/README
new file mode 100644
index 000000000..2107cc5bf
--- /dev/null
+++ b/kernel/tools/build/tests/ex/empty2/README
@@ -0,0 +1,2 @@
+This directory is left intentionally without Build file
+to test proper nesting into Build-less directories.
diff --git a/kernel/tools/build/tests/ex/ex.c b/kernel/tools/build/tests/ex/ex.c
index dc42eb2e1..57de6074d 100644
--- a/kernel/tools/build/tests/ex/ex.c
+++ b/kernel/tools/build/tests/ex/ex.c
@@ -5,6 +5,7 @@ int c(void);
 int d(void);
 int e(void);
 int f(void);
+int inc(void);
 
 int main(void)
 {
@@ -14,6 +15,7 @@ int main(void)
 	d();
 	e();
 	f();
+	inc();
 
 	return 0;
 }
diff --git a/kernel/tools/build/tests/ex/inc.c b/kernel/tools/build/tests/ex/inc.c
new file mode 100644
index 000000000..c20f1e903
--- /dev/null
+++ b/kernel/tools/build/tests/ex/inc.c
@@ -0,0 +1,8 @@
+#ifdef INCLUDE
+#include "krava.h"
+#endif
+
+int inc(void)
+{
+	return 0;
+}
diff --git a/kernel/tools/build/tests/run.sh b/kernel/tools/build/tests/run.sh
index 5494f8ea7..44d2a0fad 100755
--- a/kernel/tools/build/tests/run.sh
+++ b/kernel/tools/build/tests/run.sh
@@ -34,9 +34,36 @@ function test_ex_suffix {
 	make -C ex V=1 clean > /dev/null 2>&1
 	rm -f ex.out
 }
+
+function test_ex_include {
+	make -C ex V=1 clean > ex.out 2>&1
+
+	# build with krava.h include
+	touch ex/krava.h
+	make -C ex V=1 CFLAGS=-DINCLUDE >> ex.out 2>&1
+
+	if [ ! -x ./ex/ex ]; then
+	  echo FAILED
+	  exit -1
+	fi
+
+	# build without the include
+	rm -f ex/krava.h ex/ex
+	make -C ex V=1 >> ex.out 2>&1
+
+	if [ ! -x ./ex/ex ]; then
+	  echo FAILED
+	  exit -1
+	fi
+
+	make -C ex V=1 clean > /dev/null 2>&1
+	rm -f ex.out
+}
+
 echo -n Testing..
 
 test_ex
 test_ex_suffix
+test_ex_include
 
 echo OK