system/linux
system/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux synced 2024-07-21 02:23:16 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity
linux/arch/s390/boot/Makefile
Sumanth Korikkar 00cda11d3b s390: Compile kernel with -fPIC and link with -no-pie 
When the kernel is built with CONFIG_PIE_BUILD option enabled it
uses dynamic symbols, for which the linker does not allow more
than 64K number of entries. This can break features like kpatch.

Hence, whenever possible the kernel is built with CONFIG_PIE_BUILD
option disabled. For that support of unaligned symbols generated by
linker scripts in the compiler is necessary.

However, older compilers might lack such support. In that case the
build process resorts to CONFIG_PIE_BUILD option-enabled build.

Compile object files with -fPIC option and then link the kernel
binary with -no-pie linker option.

As result, the dynamic symbols are not generated and not only kpatch
feature succeeds, but also the whole CONFIG_PIE_BUILD option-enabled
code could be dropped.

[ agordeev: Reworded the commit message ]

Suggested-by: Ulrich Weigand <ulrich.weigand@de.ibm.com>
Signed-off-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2024-04-29 17:33:30 +02:00

142 lines
5.1 KiB
Makefile
Raw Blame History

# SPDX-License-Identifier: GPL-2.0
#
# Makefile for the linux s390-specific parts of the memory manager.
#
KCOV_INSTRUMENT := n
GCOV_PROFILE := n
UBSAN_SANITIZE := n
KASAN_SANITIZE := n
KCSAN_SANITIZE := n
KBUILD_AFLAGS := $(KBUILD_AFLAGS_DECOMPRESSOR)
KBUILD_CFLAGS := $(KBUILD_CFLAGS_DECOMPRESSOR)
#
# Use minimum architecture for als.c to be able to print an error
# message if the kernel is started on a machine which is too old
#
ifndef CONFIG_CC_IS_CLANG
CC_FLAGS_MARCH_MINIMUM := -march=z900
else
CC_FLAGS_MARCH_MINIMUM := -march=z10
endif
ifneq ($(CC_FLAGS_MARCH),$(CC_FLAGS_MARCH_MINIMUM))
AFLAGS_REMOVE_head.o += $(CC_FLAGS_MARCH)
AFLAGS_head.o += $(CC_FLAGS_MARCH_MINIMUM)
AFLAGS_REMOVE_mem.o += $(CC_FLAGS_MARCH)
AFLAGS_mem.o += $(CC_FLAGS_MARCH_MINIMUM)
CFLAGS_REMOVE_als.o += $(CC_FLAGS_MARCH)
CFLAGS_als.o += $(CC_FLAGS_MARCH_MINIMUM)
CFLAGS_REMOVE_sclp_early_core.o += $(CC_FLAGS_MARCH)
CFLAGS_sclp_early_core.o += $(CC_FLAGS_MARCH_MINIMUM)
endif
CFLAGS_sclp_early_core.o += -I$(srctree)/drivers/s390/char
obj-y := head.o als.o startup.o physmem_info.o ipl_parm.o ipl_report.o vmem.o
obj-y += string.o ebcdic.o sclp_early_core.o mem.o ipl_vmparm.o cmdline.o
obj-y += version.o pgm_check_info.o ctype.o ipl_data.o relocs.o
obj-$(findstring y, $(CONFIG_PROTECTED_VIRTUALIZATION_GUEST) $(CONFIG_PGSTE)) += uv.o
obj-$(CONFIG_RANDOMIZE_BASE) += kaslr.o
obj-y += $(if $(CONFIG_KERNEL_UNCOMPRESSED),,decompressor.o) info.o
obj-$(CONFIG_KERNEL_ZSTD) += clz_ctz.o
obj-all := $(obj-y) piggy.o syms.o
targets := bzImage section_cmp.boot.data section_cmp.boot.preserved.data $(obj-y)
targets += vmlinux.lds vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2
targets += vmlinux.bin.xz vmlinux.bin.lzma vmlinux.bin.lzo vmlinux.bin.lz4
targets += vmlinux.bin.zst info.bin syms.bin vmlinux.syms $(obj-all)
targets += relocs.S
OBJECTS := $(addprefix $(obj)/,$(obj-y))
OBJECTS_ALL := $(addprefix $(obj)/,$(obj-all))
clean-files += vmlinux.map
quiet_cmd_section_cmp = SECTCMP $*
define cmd_section_cmp
s1=`$(OBJDUMP) -t "$<" | grep "\s$*\s\+" | sort | \
sed -n "/0000000000000000/! s/.*\s$*\s\+//p" | sha256sum`; \
s2=`$(OBJDUMP) -t "$(word 2,$^)" | grep "\s$*\s\+" | sort | \
sed -n "/0000000000000000/! s/.*\s$*\s\+//p" | sha256sum`; \
if [ "$$s1" != "$$s2" ]; then \
echo "error: section $* differs between $< and $(word 2,$^)" >&2; \
exit 1; \
fi; \
touch $@
endef
$(obj)/bzImage: $(obj)/vmlinux $(obj)/section_cmp.boot.data $(obj)/section_cmp.boot.preserved.data FORCE
$(call if_changed,objcopy)
$(obj)/section_cmp%: vmlinux $(obj)/vmlinux FORCE
$(call if_changed,section_cmp)
LDFLAGS_vmlinux-$(CONFIG_LD_ORPHAN_WARN) := --orphan-handling=$(CONFIG_LD_ORPHAN_WARN_LEVEL)
LDFLAGS_vmlinux := $(LDFLAGS_vmlinux-y) --oformat $(LD_BFD) -e startup $(if $(CONFIG_VMLINUX_MAP),-Map=$(obj)/vmlinux.map) --build-id=sha1 -T
$(obj)/vmlinux: $(obj)/vmlinux.lds $(OBJECTS_ALL) FORCE
$(call if_changed,ld)
LDFLAGS_vmlinux.syms := $(LDFLAGS_vmlinux-y) --oformat $(LD_BFD) -e startup -T
$(obj)/vmlinux.syms: $(obj)/vmlinux.lds $(OBJECTS) FORCE
$(call if_changed,ld)
quiet_cmd_dumpsyms = DUMPSYMS $<
define cmd_dumpsyms
$(NM) -n -S --format=bsd "$<" | sed -nE 's/^0*([0-9a-fA-F]+) 0*([0-9a-fA-F]+) [tT] ([^ ]*)$$/\1 \2 \3/p' | tr '\n' '\0' > "$@"
endef
$(obj)/syms.bin: $(obj)/vmlinux.syms FORCE
$(call if_changed,dumpsyms)
OBJCOPYFLAGS_syms.o := -I binary -O elf64-s390 -B s390:64-bit --rename-section .data=.decompressor.syms
$(obj)/syms.o: $(obj)/syms.bin FORCE
$(call if_changed,objcopy)
OBJCOPYFLAGS_info.bin := -O binary --only-section=.vmlinux.info --set-section-flags .vmlinux.info=alloc,load
$(obj)/info.bin: vmlinux FORCE
$(call if_changed,objcopy)
OBJCOPYFLAGS_info.o := -I binary -O elf64-s390 -B s390:64-bit --rename-section .data=.vmlinux.info
$(obj)/info.o: $(obj)/info.bin FORCE
$(call if_changed,objcopy)
OBJCOPYFLAGS_vmlinux.bin := -O binary --remove-section=.comment --remove-section=.vmlinux.info -S
$(obj)/vmlinux.bin: vmlinux FORCE
$(call if_changed,objcopy)
CMD_RELOCS=arch/s390/tools/relocs
quiet_cmd_relocs = RELOCS $@
cmd_relocs = $(CMD_RELOCS) $< > $@
$(obj)/relocs.S: vmlinux FORCE
$(call if_changed,relocs)
suffix-$(CONFIG_KERNEL_GZIP) := .gz
suffix-$(CONFIG_KERNEL_BZIP2) := .bz2
suffix-$(CONFIG_KERNEL_LZ4) := .lz4
suffix-$(CONFIG_KERNEL_LZMA) := .lzma
suffix-$(CONFIG_KERNEL_LZO) := .lzo
suffix-$(CONFIG_KERNEL_XZ) := .xz
suffix-$(CONFIG_KERNEL_ZSTD) := .zst
$(obj)/vmlinux.bin.gz: $(obj)/vmlinux.bin FORCE
$(call if_changed,gzip)
$(obj)/vmlinux.bin.bz2: $(obj)/vmlinux.bin FORCE
$(call if_changed,bzip2_with_size)
$(obj)/vmlinux.bin.lz4: $(obj)/vmlinux.bin FORCE
$(call if_changed,lz4_with_size)
$(obj)/vmlinux.bin.lzma: $(obj)/vmlinux.bin FORCE
$(call if_changed,lzma_with_size)
$(obj)/vmlinux.bin.lzo: $(obj)/vmlinux.bin FORCE
$(call if_changed,lzo_with_size)
$(obj)/vmlinux.bin.xz: $(obj)/vmlinux.bin FORCE
$(call if_changed,xzkern_with_size)
$(obj)/vmlinux.bin.zst: $(obj)/vmlinux.bin FORCE
$(call if_changed,zstd22_with_size)
OBJCOPYFLAGS_piggy.o := -I binary -O elf64-s390 -B s390:64-bit --rename-section .data=.vmlinux.bin.compressed
$(obj)/piggy.o: $(obj)/vmlinux.bin$(suffix-y) FORCE
$(call if_changed,objcopy)
Reference in a new issue View git blame Copy permalink