Commit 0bf62763 authored by H. Peter Anvin's avatar H. Peter Anvin
Browse files

x32: Warn and disable rather than error if binutils too old 



If X32 is enabled in .config, but the binutils can't build it, issue a
warning and disable the feature rather than erroring out.

In order to support this, have CONFIG_X86_X32 be the option set in
Kconfig, and CONFIG_X86_X32_ABI be the option set by the Makefile when
it is enabled and binutils has been found to be functional.

Requested-by: default avatarIngo Molnar <mingo@elte.hu>
Signed-off-by: default avatarH. Peter Anvin <hpa@linux.intel.com>
Cc: H. J. Lu <hjl.tools@gmail.com>
Link: http://lkml.kernel.org/r/1329696488-16970-1-git-send-email-hpa@zytor.com
parent e0a449ca

arch/x86/Kconfig

+2 −2
Original line number Diff line number Diff line
@@ -2175,7 +2175,7 @@ config IA32_AOUT 
	---help---

	  Support old a.out binaries in the 32bit emulation.



config X86_X32_ABI

config X86_X32

	bool "x32 ABI for 64-bit mode (EXPERIMENTAL)"

	depends on X86_64 && IA32_EMULATION && EXPERIMENTAL

	---help---
@@ -2190,7 +2190,7 @@ config X86_X32_ABI 


config COMPAT

	def_bool y

	depends on IA32_EMULATION || X86_X32_ABI

	depends on IA32_EMULATION || X86_X32



config COMPAT_FOR_U64_ALIGNMENT

	def_bool COMPAT

arch/x86/Makefile

+16 −0
Original line number Diff line number Diff line
@@ -82,6 +82,22 @@ ifdef CONFIG_CC_STACKPROTECTOR 
        endif

endif



ifdef CONFIG_X86_X32

	x32_ld_ok := $(call try-run,\

			/bin/echo -e '1: .quad 1b' | \

			$(CC) $(KBUILD_AFLAGS) -c -xassembler -o "$$TMP" - && \

			$(OBJCOPY) -O elf32-x86-64 "$$TMP" "$$TMPO" && \

			$(LD) -m elf32_x86_64 "$$TMPO" -o "$$TMP",y,n)

	ifeq ($(x32_ld_ok),y)

		CONFIG_X86_X32_ABI := y

		KBUILD_AFLAGS += -DCONFIG_X86_X32_ABI

		KBUILD_CFLAGS += -DCONFIG_X86_X32_ABI

	else

		$(warning CONFIG_X86_X32 enabled but no binutils support)

	endif

endif

export CONFIG_X86_X32_ABI



# Don't unroll struct assignments with kmemcheck enabled

ifeq ($(CONFIG_KMEMCHECK),y)

	KBUILD_CFLAGS += $(call cc-option,-fno-builtin-memcpy)

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