On Wed, Jul 06, 2016 at 06:57:39PM +0100, Catalin Marinas wrote: > 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. > > -----------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 This didn't work either. Basically, when building arch/arm64/kernel/signal.o for example, it doesn't figure out that vdso-offsets.h has additional dependencies like the vdso.so.dbg so that it builds the vdso object first. I'll look for a little longer, maybe I find a better workaround. -- Catalin -- 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
