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# SPDX-License-Identifier: GPL-2.0-only
# Copied from arch/tile/kernel/vdso/Makefile
# Absolute relocation type $(ARCH_REL_TYPE_ABS) needs to be defined before
# the inclusion of generic Makefile.
ARCH_REL_TYPE_ABS := R_RISCV_32|R_RISCV_64|R_RISCV_JUMP_SLOT
include $(srctree)/lib/vdso/Makefile
# Symbols present in the vdso
vdso-syms = rt_sigreturn
ifdef CONFIG_64BIT
vdso-syms += vgettimeofday
endif
vdso-syms += getcpu
vdso-syms += flush_icache
# Files to link into the vdso
obj-vdso = $(patsubst %, %.o, $(vdso-syms)) note.o
ccflags-y := -fno-stack-protector
ifneq ($(c-gettimeofday-y),)
CFLAGS_vgettimeofday.o += -fPIC -include $(c-gettimeofday-y)
endif
# Build rules
targets := $(obj-vdso) vdso.so vdso.so.dbg vdso.lds vdso-syms.S
obj-vdso := $(addprefix $(obj)/, $(obj-vdso))
obj-y += vdso.o vdso-syms.o
CPPFLAGS_vdso.lds += -P -C -U$(ARCH)
# Disable -pg to prevent insert call site
CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -Os
# Disable profiling and instrumentation for VDSO code
GCOV_PROFILE := n
KCOV_INSTRUMENT := n
KASAN_SANITIZE := n
# Force dependency
$(obj)/vdso.o: $(obj)/vdso.so
# link rule for the .so file, .lds has to be first
$(obj)/vdso.so.dbg: $(obj)/vdso.lds $(obj-vdso) FORCE
$(call if_changed,vdsold)
LDFLAGS_vdso.so.dbg = -shared -s -soname=linux-vdso.so.1 \
--build-id=sha1 --hash-style=both --eh-frame-hdr
# We also create a special relocatable object that should mirror the symbol
# table and layout of the linked DSO. With ld --just-symbols we can then
# refer to these symbols in the kernel code rather than hand-coded addresses.
$(obj)/vdso-syms.S: $(obj)/vdso.so FORCE
$(call if_changed,so2s)
# strip rule for the .so file
$(obj)/%.so: OBJCOPYFLAGS := -S
$(obj)/%.so: $(obj)/%.so.dbg FORCE
$(call if_changed,objcopy)
# actual build commands
# The DSO images are built using a special linker script
# Make sure only to export the intended __vdso_xxx symbol offsets.
quiet_cmd_vdsold = VDSOLD $@
cmd_vdsold = $(LD) $(ld_flags) -T $(filter-out FORCE,$^) -o $@.tmp && \
$(OBJCOPY) $(patsubst %, -G __vdso_%, $(vdso-syms)) $@.tmp $@ && \
rm $@.tmp
# Extracts symbol offsets from the VDSO, converting them into an assembly file
# that contains the same symbols at the same offsets.
quiet_cmd_so2s = SO2S $@
cmd_so2s = $(NM) -D $< | $(srctree)/$(src)/so2s.sh > $@
# install commands for the unstripped file
quiet_cmd_vdso_install = INSTALL $@
cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@
vdso.so: $(obj)/vdso.so.dbg
@mkdir -p $(MODLIB)/vdso
$(call cmd,vdso_install)
vdso_install: vdso.so
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