linux/arch/s390/boot/Makefile
Heiko Carstens 80ddf5ce1c s390: always build relocatable kernel
Nathan Chancellor reported several link errors on s390 with
CONFIG_RELOCATABLE disabled, after binutils commit 906f69cf65da ("IBM
zSystems: Issue error for *DBL relocs on misaligned symbols"). The binutils
commit reveals potential miscompiles that might have happened already
before with linker script defined symbols at odd addresses.

A similar bug was recently fixed in the kernel with commit c9305b6c1f
("s390: fix nospec table alignments").

See https://github.com/ClangBuiltLinux/linux/issues/1747 for an analysis
from Ulich Weigand.

Therefore always build a relocatable kernel to avoid this problem. There is
hardly any use-case for non-relocatable kernels, so this shouldn't be
controversial.

Link: https://github.com/ClangBuiltLinux/linux/issues/1747
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Reported-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20221030182202.2062705-1-hca@linux.ibm.com
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2022-11-08 19:32:32 +01:00

132 lines
4.7 KiB
Makefile

# 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 mem_detect.o ipl_parm.o ipl_report.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 machine_kexec_reloc.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)
OBJECTS := $(addprefix $(obj)/,$(obj-y))
OBJECTS_ALL := $(addprefix $(obj)/,$(obj-all))
quiet_cmd_section_cmp = SECTCMP $*
define cmd_section_cmp
s1=`$(OBJDUMP) -t -j "$*" "$<" | sort | \
sed -n "/0000000000000000/! s/.*\s$*\s\+//p" | sha256sum`; \
s2=`$(OBJDUMP) -t -j "$*" "$(word 2,$^)" | sort | \
sed -n "/0000000000000000/! s/.*\s$*\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 := --oformat $(LD_BFD) -e startup --build-id=sha1 -T
$(obj)/vmlinux: $(obj)/vmlinux.lds $(OBJECTS_ALL) FORCE
$(call if_changed,ld)
LDFLAGS_vmlinux.syms := --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=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
$(call if_changed,objcopy)
suffix-$(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)