mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-21 16:29:59 +00:00
![Ard Biesheuvel](/assets/img/avatar_default.png)
GNU ld used to set the ELF file type to ET_DYN for PIE executables, which is the same file type used for shared libraries. However, this was changed recently, and now PIE executables are emitted as ET_EXEC instead. The distinction is only relevant for ELF loaders, and so there is little reason to care about the difference when building the kernel, which is why the change has gone unnoticed until now. However, debuggers do use the ELF binary, and expect ET_EXEC type files to appear in memory at the exact offset described in the ELF metadata. This means source level debugging is no longer possible when KASLR is in effect or when executing the stub. So add the -shared LD option when building with CONFIG_RELOCATABLE=y. This forces the ELF file type to be set to ET_DYN (which is what you get when building with binutils 2.24 and earlier anyway), and has no other ill effects. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
153 lines
4.5 KiB
Makefile
153 lines
4.5 KiB
Makefile
#
|
|
# arch/arm64/Makefile
|
|
#
|
|
# This file is included by the global makefile so that you can add your own
|
|
# architecture-specific flags and dependencies.
|
|
#
|
|
# This file is subject to the terms and conditions of the GNU General Public
|
|
# License. See the file "COPYING" in the main directory of this archive
|
|
# for more details.
|
|
#
|
|
# Copyright (C) 1995-2001 by Russell King
|
|
|
|
LDFLAGS_vmlinux :=-p --no-undefined -X
|
|
CPPFLAGS_vmlinux.lds = -DTEXT_OFFSET=$(TEXT_OFFSET)
|
|
GZFLAGS :=-9
|
|
|
|
ifneq ($(CONFIG_RELOCATABLE),)
|
|
LDFLAGS_vmlinux += -pie -shared -Bsymbolic
|
|
endif
|
|
|
|
ifeq ($(CONFIG_ARM64_ERRATUM_843419),y)
|
|
ifeq ($(call ld-option, --fix-cortex-a53-843419),)
|
|
$(warning ld does not support --fix-cortex-a53-843419; kernel may be susceptible to erratum)
|
|
else
|
|
LDFLAGS_vmlinux += --fix-cortex-a53-843419
|
|
endif
|
|
endif
|
|
|
|
KBUILD_DEFCONFIG := defconfig
|
|
|
|
# Check for binutils support for specific extensions
|
|
lseinstr := $(call as-instr,.arch_extension lse,-DCONFIG_AS_LSE=1)
|
|
|
|
ifeq ($(CONFIG_ARM64_LSE_ATOMICS), y)
|
|
ifeq ($(lseinstr),)
|
|
$(warning LSE atomics not supported by binutils)
|
|
endif
|
|
endif
|
|
|
|
KBUILD_CFLAGS += -mgeneral-regs-only $(lseinstr)
|
|
KBUILD_CFLAGS += -fno-asynchronous-unwind-tables
|
|
KBUILD_CFLAGS += $(call cc-option, -mpc-relative-literal-loads)
|
|
KBUILD_AFLAGS += $(lseinstr)
|
|
|
|
ifeq ($(CONFIG_CPU_BIG_ENDIAN), y)
|
|
KBUILD_CPPFLAGS += -mbig-endian
|
|
AS += -EB
|
|
LD += -EB
|
|
UTS_MACHINE := aarch64_be
|
|
else
|
|
KBUILD_CPPFLAGS += -mlittle-endian
|
|
AS += -EL
|
|
LD += -EL
|
|
UTS_MACHINE := aarch64
|
|
endif
|
|
|
|
CHECKFLAGS += -D__aarch64__
|
|
|
|
ifeq ($(CONFIG_ARM64_MODULE_CMODEL_LARGE), y)
|
|
KBUILD_CFLAGS_MODULE += -mcmodel=large
|
|
endif
|
|
|
|
ifeq ($(CONFIG_ARM64_MODULE_PLTS),y)
|
|
KBUILD_LDFLAGS_MODULE += -T $(srctree)/arch/arm64/kernel/module.lds
|
|
endif
|
|
|
|
# Default value
|
|
head-y := arch/arm64/kernel/head.o
|
|
|
|
# The byte offset of the kernel image in RAM from the start of RAM.
|
|
ifeq ($(CONFIG_ARM64_RANDOMIZE_TEXT_OFFSET), y)
|
|
TEXT_OFFSET := $(shell awk "BEGIN {srand(); printf \"0x%06x\n\", \
|
|
int(2 * 1024 * 1024 / (2 ^ $(CONFIG_ARM64_PAGE_SHIFT)) * \
|
|
rand()) * (2 ^ $(CONFIG_ARM64_PAGE_SHIFT))}")
|
|
else
|
|
TEXT_OFFSET := 0x00080000
|
|
endif
|
|
|
|
# KASAN_SHADOW_OFFSET = VA_START + (1 << (VA_BITS - 3)) - (1 << 61)
|
|
# in 32-bit arithmetic
|
|
KASAN_SHADOW_OFFSET := $(shell printf "0x%08x00000000\n" $$(( \
|
|
(0xffffffff & (-1 << ($(CONFIG_ARM64_VA_BITS) - 32))) \
|
|
+ (1 << ($(CONFIG_ARM64_VA_BITS) - 32 - 3)) \
|
|
- (1 << (64 - 32 - 3)) )) )
|
|
|
|
export TEXT_OFFSET GZFLAGS
|
|
|
|
core-y += arch/arm64/kernel/ arch/arm64/mm/
|
|
core-$(CONFIG_NET) += arch/arm64/net/
|
|
core-$(CONFIG_KVM) += arch/arm64/kvm/
|
|
core-$(CONFIG_XEN) += arch/arm64/xen/
|
|
core-$(CONFIG_CRYPTO) += arch/arm64/crypto/
|
|
libs-y := arch/arm64/lib/ $(libs-y)
|
|
core-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a
|
|
|
|
# Default target when executing plain make
|
|
KBUILD_IMAGE := Image.gz
|
|
KBUILD_DTBS := dtbs
|
|
|
|
all: $(KBUILD_IMAGE) $(KBUILD_DTBS)
|
|
|
|
boot := arch/arm64/boot
|
|
|
|
Image: vmlinux
|
|
$(Q)$(MAKE) $(build)=$(boot) $(boot)/$@
|
|
|
|
Image.%: Image
|
|
$(Q)$(MAKE) $(build)=$(boot) $(boot)/$@
|
|
|
|
zinstall install:
|
|
$(Q)$(MAKE) $(build)=$(boot) $@
|
|
|
|
%.dtb: scripts
|
|
$(Q)$(MAKE) $(build)=$(boot)/dts $(boot)/dts/$@
|
|
|
|
PHONY += dtbs dtbs_install
|
|
|
|
dtbs: prepare scripts
|
|
$(Q)$(MAKE) $(build)=$(boot)/dts
|
|
|
|
dtbs_install:
|
|
$(Q)$(MAKE) $(dtbinst)=$(boot)/dts
|
|
|
|
PHONY += vdso_install
|
|
vdso_install:
|
|
$(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso $@
|
|
|
|
# We use MRPROPER_FILES and CLEAN_FILES now
|
|
archclean:
|
|
$(Q)$(MAKE) $(clean)=$(boot)
|
|
$(Q)$(MAKE) $(clean)=$(boot)/dts
|
|
|
|
# We need to generate vdso-offsets.h before compiling certain files in kernel/.
|
|
# In order to do that, we should use the archprepare target, but we can't since
|
|
# asm-offsets.h is included in some files used to generate vdso-offsets.h, and
|
|
# asm-offsets.h is built in prepare0, for which archprepare is a dependency.
|
|
# Therefore we need to generate the header after prepare0 has been made, hence
|
|
# this hack.
|
|
prepare: vdso_prepare
|
|
vdso_prepare: prepare0
|
|
$(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso include/generated/vdso-offsets.h
|
|
|
|
define archhelp
|
|
echo '* Image.gz - Compressed kernel image (arch/$(ARCH)/boot/Image.gz)'
|
|
echo ' Image - Uncompressed kernel image (arch/$(ARCH)/boot/Image)'
|
|
echo '* dtbs - Build device tree blobs for enabled boards'
|
|
echo ' dtbs_install - Install dtbs to $(INSTALL_DTBS_PATH)'
|
|
echo ' install - Install uncompressed kernel'
|
|
echo ' zinstall - Install compressed kernel'
|
|
echo ' Install using (your) ~/bin/installkernel or'
|
|
echo ' (distribution) /sbin/installkernel or'
|
|
echo ' install to $$(INSTALL_PATH) and run lilo'
|
|
endef
|