x86/build: Move max-page-size option to LDFLAGS_vmlinux (587af649) · Commits · 戴 / test

This option is only required for vmlinux on 64-bit, to enforce 2MiB alignment, so set it in LDFLAGS_vmlinux instead of KBUILD_LDFLAGS. Also drop the ld-option check: this option was added in binutils-2.18 and all the other places that use it already don't have the check. This reduces the size of the intermediate ELF files arch/x86/boot/setup.elf and arch/x86/realmode/rm/realmode.elf by about 2MiB each. The binary versions are unchanged. Move the LDFLAGS settings to all be together and just after CFLAGS settings are done. Signed-off-by:

Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by:

Ingo Molnar <mingo@kernel.org> Tested-by:

Sedat Dilek <sedat.dilek@gmail.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Michal Marek <michal.lkml@markovi.net> Link: https://lore.kernel.org/r/20200722184334.3785418-1-nivedita@alum.mit.edu

arch/x86/Makefile

+17 −15

Original line number	Diff line number	Diff line
		@@ -47,10 +47,6 @@ export REALMODE_CFLAGS
		# e.g.: obj-y += foo_$(BITS).o
		export BITS

		ifdef CONFIG_X86_NEED_RELOCS
		LDFLAGS_vmlinux := --emit-relocs --discard-none
		endif

		#
		# Prevent GCC from generating any FP code by mistake.
		#
		@@ -177,17 +173,6 @@ ifeq ($(ACCUMULATE_OUTGOING_ARGS), 1)
		KBUILD_CFLAGS += $(call cc-option,-maccumulate-outgoing-args,)
		endif

		KBUILD_LDFLAGS := -m elf_$(UTS_MACHINE)

		#
		# The 64-bit kernel must be aligned to 2MB. Pass -z max-page-size=0x200000 to
		# the linker to force 2MB page size regardless of the default page size used
		# by the linker.
		#
		ifdef CONFIG_X86_64
		KBUILD_LDFLAGS += $(call ld-option, -z max-page-size=0x200000)
		endif

		# Workaround for a gcc prelease that unfortunately was shipped in a suse release
		KBUILD_CFLAGS += -Wno-sign-compare
		#
		@@ -207,6 +192,23 @@ ifdef CONFIG_RETPOLINE
		endif
		endif

		KBUILD_LDFLAGS := -m elf_$(UTS_MACHINE)

		ifdef CONFIG_X86_NEED_RELOCS
		LDFLAGS_vmlinux := --emit-relocs --discard-none
		else
		LDFLAGS_vmlinux :=
		endif

		#
		# The 64-bit kernel must be aligned to 2MB. Pass -z max-page-size=0x200000 to
		# the linker to force 2MB page size regardless of the default page size used
		# by the linker.
		#
		ifdef CONFIG_X86_64
		LDFLAGS_vmlinux += -z max-page-size=0x200000
		endif

		archscripts: scripts_basic
		$(Q)$(MAKE) $(build)=arch/x86/tools relocs

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