Re: [PATCH v2 2/3] Makefile: support flag -fsanitizer-coverage=trace-cmp

[Andrey Ryabinin]

On 10/09/2017 06:05 PM, Alexander Potapenko wrote:

> v2: - updated KCOV_ENABLE_COMPARISONS description
> ---
>  Makefile             |  5 +++--
>  lib/Kconfig.debug    | 10 ++++++++++
>  scripts/Makefile.lib |  6 ++++++
>  3 files changed, 19 insertions(+), 2 deletions(-)
> 
> diff --git a/Makefile b/Makefile
> index 2835863bdd5a..c2a8e56df748 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -374,7 +374,7 @@ AFLAGS_KERNEL	=
>  LDFLAGS_vmlinux =
>  CFLAGS_GCOV	:= -fprofile-arcs -ftest-coverage -fno-tree-loop-im $(call cc-disable-warning,maybe-uninitialized,)
>  CFLAGS_KCOV	:= $(call cc-option,-fsanitize-coverage=trace-pc,)
> -
> +CFLAGS_KCOV_COMPS := $(call cc-option,-fsanitize-coverage=trace-cmp,)
>  
>  # Use USERINCLUDE when you must reference the UAPI directories only.
>  USERINCLUDE    := \
> @@ -420,7 +420,7 @@ export MAKE AWK GENKSYMS INSTALLKERNEL PERL PYTHON UTS_MACHINE
>  export HOSTCXX HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
>  
>  export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS LDFLAGS
> -export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE CFLAGS_GCOV CFLAGS_KCOV CFLAGS_KASAN CFLAGS_UBSAN
> +export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE CFLAGS_GCOV CFLAGS_KCOV CFLAGS_KCOV_COMPS CFLAGS_KASAN CFLAGS_UBSAN
>  export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
>  export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
>  export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
> @@ -822,6 +822,7 @@ KBUILD_CFLAGS   += $(call cc-option,-Werror=designated-init)
>  KBUILD_ARFLAGS := $(call ar-option,D)
>  
>  include scripts/Makefile.kasan
> +include scripts/Makefile.kcov

scripts/Makefile.kcov doesn't exist.



> diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
> index 5e975fee0f5b..7ddd5932c832 100644
> --- a/scripts/Makefile.lib
> +++ b/scripts/Makefile.lib
> @@ -142,6 +142,12 @@ _c_flags += $(if $(patsubst n%,, \
>  	$(CFLAGS_KCOV))
>  endif
>  
> +ifeq ($(CONFIG_KCOV_ENABLE_COMPARISONS),y)
> +_c_flags += $(if $(patsubst n%,, \
> +	$(KCOV_INSTRUMENT_$(basetarget).o)$(KCOV_INSTRUMENT)$(CONFIG_KCOV_INSTRUMENT_ALL)), \
> +	$(CFLAGS_KCOV_COMPS))
> +endif
> +

Instead of this you could simply add -fsanitize-coverage=trace-cmp to CFLAGS_KCOV.


>  # If building the kernel in a separate objtree expand all occurrences
>  # of -Idir to -I$(srctree)/dir except for absolute paths (starting with '/').
>  
>