ARM: 8344/1: VDSO: honor CONFIG_VDSO in Makefile

When CONFIG_VDSO=n, the build normally does not enter arch/arm/vdso/
because arch/arm/Makefile does not add it to core-y.

However, if the user runs 'make arch/arm/vdso/' the VDSO targets will
get visited.  This is because the VDSO Makefile itself does not
consider the value of CONFIG_VDSO.

It is arguably better and more consistent behavior to generate an
empty built-in.o when CONFIG_VDSO=n and the user attempts to build
arch/arm/vdso/.  It's nicer because it doesn't try to build things
that Kconfig dependencies are there to prevent (e.g. the dependency on
AEABI), and it's less confusing than building objects that won't be
used in the final image.

Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

diff --git a/arch/arm/vdso/Makefile b/arch/arm/vdso/Makefile
index bab0a8be79247121bf20006254d49fbc943f3ba0..8aa7910510299b0dd6e10190209c330285de2449 100644 (file)
--- a/arch/arm/vdso/Makefile
+++ b/arch/arm/vdso/Makefile
@@ -10,8 +10,8 @@ ccflags-y := -shared -fPIC -fno-common -fno-builtin -fno-stack-protector
 ccflags-y += -nostdlib -Wl,-soname=linux-vdso.so.1 -DDISABLE_BRANCH_PROFILING
 ccflags-y += -Wl,--no-undefined $(call cc-ldoption, -Wl$(comma)--hash-style=sysv)
 
-obj-y += vdso.o
-extra-y += vdso.lds
+obj-$(CONFIG_VDSO) += vdso.o
+extra-$(CONFIG_VDSO) += vdso.lds
 CPPFLAGS_vdso.lds += -P -C -U$(ARCH)
 
 CFLAGS_REMOVE_vdso.o = -pg