Re: [XEN][PATCH] coverage: add extended coverage capabilities

[Grygorii Strashko <grygorii_strashko@xxxxxxxx>]

On 04.12.25 12:02, Andrew Cooper wrote:
> On 03/12/2025 10:24 pm, Grygorii Strashko wrote:
> > From: Grygorii Strashko <grygorii_strashko@xxxxxxxx>
> >
> > Added CONFIG_COVERAGE_EXTENDED to enable coverage for .init and lib code.
> > When enabled - Xen .init data will not be freed.
> >
> > Signed-off-by: Grygorii Strashko <grygorii_strashko@xxxxxxxx>
> > ---
> >   xen/Kconfig.debug          | 10 ++++++++++
> >   xen/Rules.mk               | 13 +++++++++++++
> >   xen/arch/arm/setup.c       |  2 ++
> >   xen/arch/x86/setup.c       |  4 ++++
> >   xen/common/libelf/Makefile |  4 +++-
> >   xen/common/libfdt/Makefile |  4 +++-
> >   6 files changed, 35 insertions(+), 2 deletions(-)
> >
> > diff --git a/xen/Kconfig.debug b/xen/Kconfig.debug
> > index d900d926c555..3e04e1a3992b 100644
> > --- a/xen/Kconfig.debug
> > +++ b/xen/Kconfig.debug
> > @@ -44,6 +44,16 @@ config COVERAGE
> >   
> >   	  If unsure, say N here.
> >   
> > +config COVERAGE_EXTENDED
> > +    bool "Extended Code coverage support"
> > +    depends on COVERAGE
> > +    default y
> > +    help
> > +      Enable Extended code coverage support which include .init and libs code.
> > +      The .init sections are not freed in this case.
> > +
> > +      If unsure, say N here.
> IMO this is unhelpful.  Noone wants to opt for the model we've got right
> now.
>
> Instead, I think we want:
>
> config RELAX_INIT_CHECK
>      bool
>
> and have CONFIG_COVERAGE select it.  There's no need for any user
> visible option here.
>
>
> > +
> >   config CONDITION_COVERAGE
> >         bool "Condition coverage support"
> >         depends on COVERAGE && CC_HAS_MCDC
> > diff --git a/xen/Rules.mk b/xen/Rules.mk
> > index 2b28d1ac3c18..6d66a2332fb0 100644
> > --- a/xen/Rules.mk
> > +++ b/xen/Rules.mk
> > @@ -260,6 +267,7 @@ $(obj)/%.o: $(src)/%.S FORCE
> >   
> >   
> >   quiet_cmd_obj_init_o = INIT_O  $@
> > +ifneq ($(CONFIG_COVERAGE_EXTENDED),y)
> >   define cmd_obj_init_o
> >       $(OBJDUMP) -h $< | while read idx name sz rest; do \
> >           case "$$name" in \
> > @@ -272,6 +280,11 @@ define cmd_obj_init_o
> >       done || exit $$?; \
> >       $(OBJCOPY) $(foreach s,$(SPECIAL_DATA_SECTIONS),--rename-section 
> > .$(s)=.init.$(s)) $< $@
> >   endef
> > +else
> > +define cmd_obj_init_o
> > +    $(OBJCOPY) $(foreach s,$(SPECIAL_DATA_SECTIONS),--rename-section 
> > .$(s)=.init.$(s)) $< $@
> > +endef
> > +endif
> This wants to be something more like:
>
> @@ -261,6 +268,7 @@ $(obj)/%.o: $(src)/%.S FORCE
>   
>   quiet_cmd_obj_init_o = INIT_O  $@
>   define cmd_obj_init_o
> +ifneq ($(CONFIG_RELAX_INIT_CHECK),y)
>       $(OBJDUMP) -h $< | while read idx name sz rest; do \
>           case "$$name" in \
>           .*.local) ;; \
> @@ -269,7 +277,8 @@ define cmd_obj_init_o
>               echo "Error: size of $<:$$name is 0x$$sz" >&2; \
>               exit $$(expr $$idx + 1);; \
>           esac; \
> -    done || exit $$?; \
> +    done || exit $$?
> +endif
>       $(OBJCOPY) $(foreach s,$(SPECIAL_DATA_SECTIONS),--rename-section 
> .$(s)=.init.$(s)) $< $@
>   endef
above diff is not working and generates build failure :(

--
Best regards,
-grygorii