[PATCH v8 21/28] KVM: arm64: Add tracing capability for the pKVM hyp

[Vincent Donnefort]

[...]

> > diff --git a/arch/arm64/kvm/hyp/nvhe/Makefile b/arch/arm64/kvm/hyp/nvhe/Makefile
> > index f55a9a17d38f..504c3b9caef8 100644
> > --- a/arch/arm64/kvm/hyp/nvhe/Makefile
> > +++ b/arch/arm64/kvm/hyp/nvhe/Makefile
> > @@ -29,7 +29,7 @@ hyp-obj-y += ../vgic-v3-sr.o ../aarch32.o ../vgic-v2-cpuif-proxy.o ../entry.o \
> >  	 ../fpsimd.o ../hyp-entry.o ../exception.o ../pgtable.o
> >  hyp-obj-y += ../../../kernel/smccc-call.o
> >  hyp-obj-$(CONFIG_LIST_HARDENED) += list_debug.o
> > -hyp-obj-$(CONFIG_PKVM_TRACING) += clock.o
> > +hyp-obj-$(CONFIG_PKVM_TRACING) += clock.o trace.o ../../../../../kernel/trace/simple_ring_buffer.o
> 
> Can we get something less awful here? Surely there is a way to get an
> absolute path from the kbuild infrastructure? $(objtree) springs to
> mind...

Because of the path substitution below, I can't simply use $(objtree) here. I
suppose that's why all other paths above are relative.

However, I could probably simplify by including simple_ring_buffer.c into trace.c:

  diff --git a/arch/arm64/kvm/hyp/nvhe/Makefile b/arch/arm64/kvm/hyp/nvhe/Makefile
  -hyp-obj-$(CONFIG_TRACING) += clock.o trace.o ../../../../../kernel/trace/simple_ring_buffer.o
  +hyp-obj-$(CONFIG_TRACING) += clock.o trace.o
   hyp-obj-y += $(lib-objs)
   
  +# Path to simple_ring_buffer.c
  +CFLAGS_trace.nvhe.o += -I$(objtree)/kernel/trace/
  +
  
  
  diff --git a/arch/arm64/kvm/hyp/nvhe/trace.c b/arch/arm64/kvm/hyp/nvhe/trace.c
  -#include <linux/simple_ring_buffer.h>
  +#include "simple_ring_buffer.c"

> 
> >  hyp-obj-y += $(lib-objs)
> >  
> >  ##
> > diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-main.c b/arch/arm64/kvm/hyp/nvhe/hyp-main.c

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