[PATCH v17 02/24] selftests: vm: pkeys: Fix multilib builds for x86

[Sandipan Das]

This ensures that both 32-bit and 64-bit binaries are generated
when this is built on a x86_64 system. Most of the changes have
been borrowed from tools/testing/selftests/x86/Makefile.

Signed-off-by: Sandipan Das <sandipan at linux.ibm.com>
---
 tools/testing/selftests/vm/Makefile | 49 +++++++++++++++++++++++++++++
 1 file changed, 49 insertions(+)

diff --git a/tools/testing/selftests/vm/Makefile b/tools/testing/selftests/vm/Makefile
index 4e9c741be6af..7fa0adf11f6a 100644
--- a/tools/testing/selftests/vm/Makefile
+++ b/tools/testing/selftests/vm/Makefile
@@ -18,7 +18,56 @@ TEST_GEN_FILES += on-fault-limit
 TEST_GEN_FILES += thuge-gen
 TEST_GEN_FILES += transhuge-stress
 TEST_GEN_FILES += userfaultfd
+
+ifeq ($(ARCH), x86_64)
+CAN_BUILD_I386 := $(shell ./../x86/check_cc.sh $(CC) ../x86/trivial_32bit_program.c -m32)
+CAN_BUILD_X86_64 := $(shell ./../x86/check_cc.sh $(CC) ../x86/trivial_64bit_program.c)
+CAN_BUILD_WITH_NOPIE := $(shell ./../x86/check_cc.sh $(CC) ../x86/trivial_program.c -no-pie)
+
+TARGETS := protection_keys
+BINARIES_32 := $(TARGETS:%=%_32)
+BINARIES_64 := $(TARGETS:%=%_64)
+
+.PHONY: $(TARGETS)
+
+ifeq ($(CAN_BUILD_WITH_NOPIE),1)
+CFLAGS += -no-pie
+endif
+
+ifeq ($(CAN_BUILD_I386),1)
+TEST_GEN_FILES += $(BINARIES_32)
+$(TARGETS): $(BINARIES_32)
+$(BINARIES_32): %_32: %.c
+	$(CC) -m32 -o $@ $(CFLAGS) $(EXTRA_CFLAGS) $^ -lrt -ldl -lm
+endif
+
+ifeq ($(CAN_BUILD_X86_64),1)
+TEST_GEN_FILES += $(BINARIES_64)
+$(TARGETS): $(BINARIES_64)
+$(BINARIES_64): %_64: %.c
+	$(CC) -m64 -o $@ $(CFLAGS) $(EXTRA_CFLAGS) $^ -lrt -ldl
+endif
+
+# x86_64 users should be encouraged to install 32-bit libraries
+ifeq ($(CAN_BUILD_I386)$(CAN_BUILD_X86_64),01)
+$(TARGETS): warn_32bit_failure
+
+warn_32bit_failure:
+	@echo "Warning: you seem to have a broken 32-bit build" 2>&1;		\
+	echo "environment.  This will reduce test coverage of 64-bit" 2>&1;	\
+	echo "kernels.  If you are using a Debian-like distribution," 2>&1;	\
+	echo "try:"; 2>&1;							\
+	echo "";								\
+	echo "  apt-get install gcc-multilib libc6-i386 libc6-dev-i386";	\
+	echo "";								\
+	echo "If you are using a Fedora-like distribution, try:";		\
+	echo "";								\
+	echo "  yum install glibc-devel.*i686";					\
+	exit 0;
+endif
+else
 TEST_GEN_FILES += protection_keys
+endif
 
 ifneq (,$(filter $(ARCH),arm64 ia64 mips64 parisc64 ppc64 riscv64 s390x sh64 sparc64 x86_64))
 TEST_GEN_FILES += va_128TBswitch
-- 
2.17.1