From mboxrd@z Thu Jan  1 00:00:00 1970
From: Will Deacon <will.deacon@arm.com>
Subject: Re: [PATCH] kvmtool: Makefile: disable PIE build for bios and
 pre_init
Date: Wed, 26 Oct 2016 18:32:40 +0100
Message-ID: <20161026173240.GF15216@arm.com>
References: <20161024105853.20083-1-riku.voipio@linaro.org>
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To: riku.voipio@linaro.org
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On Mon, Oct 24, 2016 at 01:58:53PM +0300, riku.voipio@linaro.org wrote:
> From: Riku Voipio <riku.voipio@linaro.org>
> 
> Latest Debian and Ubuntu GCC default to PIE code. Disable
> PIE for bios and pre_init. Since the flag -no-pie is not
> available on older GCC's, make use of flag only if the
> option is available.
> 
> Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
> ---
> see: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=837545
> ---
>  Makefile | 10 ++++++++--
>  1 file changed, 8 insertions(+), 2 deletions(-)
> 
> diff --git a/Makefile b/Makefile
> index 1f0196f..0d8b66d 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -284,7 +284,7 @@ ifeq ($(call try-build,$(SOURCE_STATIC),$(CFLAGS),$(LDFLAGS) -static),y)
>  	GUEST_INIT	:= guest/init
>  	GUEST_OBJS	= guest/guest_init.o
>  	ifeq ($(ARCH_PRE_INIT),)
> -		GUEST_INIT_FLAGS	+= -static
> +		GUEST_INIT_FLAGS	+= -static $(PIE_FLAGS)
>  	else
>  		CFLAGS			+= -DCONFIG_GUEST_PRE_INIT
>  		GUEST_INIT_FLAGS	+= -DCONFIG_GUEST_PRE_INIT
> @@ -307,6 +307,10 @@ ifeq (y,$(ARCH_WANT_LIBFDT))
>  	endif
>  endif
>  
> +ifeq ($(call try-build,$(SOURCE_HELLO),$(CFLAGS),-no-pie),y)
> +	PIE_FLAGS	+= -no-pie
> +endif
> +
>  ifneq ($(NOTFOUND),)
>          $(warning Skipping optional libraries: $(NOTFOUND))
>  endif
> @@ -388,7 +392,7 @@ $(PROGRAM_ALIAS): $(PROGRAM)
>  ifneq ($(ARCH_PRE_INIT),)
>  $(GUEST_PRE_INIT): $(ARCH_PRE_INIT)
>  	$(E) "  LINK    " $@
> -	$(Q) $(CC) -s -nostdlib $(ARCH_PRE_INIT) -o $@
> +	$(Q) $(CC) -s $(PIE_FLAGS) -nostdlib $(ARCH_PRE_INIT) -o $@
>  	$(Q) $(LD) -r -b binary -o guest/guest_pre_init.o $(GUEST_PRE_INIT)
>  endif
>  
> @@ -435,6 +439,8 @@ BIOS_CFLAGS += -march=i386
>  BIOS_CFLAGS += -mregparm=3
>  
>  BIOS_CFLAGS += -fno-stack-protector
> +BIOS_CFLAGS += $(PIE-FLAGS)

Shouldn't that be an underscore? Did you test this?

Will