On Thu, May 12, 2016 at 05:39:15PM +0100, Kevin Brodsky wrote: > +# We need to generate vdso-offsets.h before compiling certain files in kernel/. > +# In order to do that, we should use the archprepare target, but we can't since > +# asm-offsets.h is included in some files used to generate vdso-offsets.h, and > +# asm-offsets.h is built in prepare0, for which archprepare is a dependency. > +# Therefore we need to generate the header after prepare0 has been made, hence > +# this hack. > +prepare: vdso_prepare > +vdso_prepare: prepare0 > + $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso include/generated/vdso-offsets.h This indeed looks dodgy. I'm not sure about the makefile rules but would the above override the "prepare" target in the top Makefile? I think a dependency problem we have is that arch/arm64/kernel/signal.o depends on include/generated/vdso-offsets.h. However, we don't have any target for the latter, only for $(objtree)arch/arm64/kernel/vdso/vdso-offsets.h which no-one is including. Because of this, we have a fake dependency in arch/arm64/kernel/Makefile. It's been a long time since I wrote makefiles but I think a simpler approach may be to just get the include/generated/vdso-offsets.h target and remove the arch/arm64/kernel/vdso/vdso-offsets.h one entirely like below. Otherwise, we give up on storing the generated file in include/generated/ and move arch/arm64/include/asm/vdso.h to arch/arm64/kernel/vdso/. -----------8<------------------------- diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile index 7700c0c23962..9bdacbf59091 100644 --- a/arch/arm64/kernel/Makefile +++ b/arch/arm64/kernel/Makefile @@ -55,5 +55,4 @@ head-y := head.o extra-y += $(head-y) vmlinux.lds # vDSO - this must be built first to generate the symbol offsets -$(call objectify,$(arm64-obj-y)): $(obj)/vdso/vdso-offsets.h -$(obj)/vdso/vdso-offsets.h: $(obj)/vdso +$(objtree)/include/generated/vdso-offsets.h: $(obj)/vdso diff --git a/arch/arm64/kernel/vdso/Makefile b/arch/arm64/kernel/vdso/Makefile index b467fd0a384b..44c20e3c9f43 100644 --- a/arch/arm64/kernel/vdso/Makefile +++ b/arch/arm64/kernel/vdso/Makefile @@ -23,7 +23,7 @@ GCOV_PROFILE := n ccflags-y += -Wl,-shared obj-y += vdso.o -extra-y += vdso.lds vdso-offsets.h +extra-y += vdso.lds ../../../../include/generated/vdso-offsets.h CPPFLAGS_vdso.lds += -P -C -U$(ARCH) # Force dependency (incbin is bad) @@ -42,11 +42,10 @@ $(obj)/%.so: $(obj)/%.so.dbg FORCE gen-vdsosym := $(srctree)/$(src)/gen_vdso_offsets.sh quiet_cmd_vdsosym = VDSOSYM $@ define cmd_vdsosym - $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@ && \ - cp $@ include/generated/ + $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@ endef -$(obj)/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE +$(obj)/../../../../include/generated/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE $(call if_changed,vdsosym) # Assembly rules for the .S files -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
