xref: /linux/arch/arm/vdso/Makefile (revision 44f57d78) 
1# SPDX-License-Identifier: GPL-2.0
2hostprogs-y := vdsomunge
3
4obj-vdso := vgettimeofday.o datapage.o
5
6# Build rules
7targets := $(obj-vdso) vdso.so vdso.so.dbg vdso.so.raw vdso.lds
8obj-vdso := $(addprefix $(obj)/, $(obj-vdso))
9
10ccflags-y := -fPIC -fno-common -fno-builtin -fno-stack-protector
11ccflags-y += -DDISABLE_BRANCH_PROFILING
12
13ldflags-$(CONFIG_CPU_ENDIAN_BE8) := --be8
14ldflags-y := -Bsymbolic --no-undefined -soname=linux-vdso.so.1 \
15	    -z max-page-size=4096 -z common-page-size=4096 \
16	    -nostdlib -shared $(ldflags-y) \
17	    $(call ld-option, --hash-style=sysv) \
18	    $(call ld-option, --build-id) \
19	    -T
20
21obj-$(CONFIG_VDSO) += vdso.o
22extra-$(CONFIG_VDSO) += vdso.lds
23CPPFLAGS_vdso.lds += -P -C -U$(ARCH)
24
25CFLAGS_REMOVE_vdso.o = -pg
26
27# Force -O2 to avoid libgcc dependencies
28CFLAGS_REMOVE_vgettimeofday.o = -pg -Os
29CFLAGS_vgettimeofday.o = -O2
30
31# Disable gcov profiling for VDSO code
32GCOV_PROFILE := n
33
34# Prevents link failures: __sanitizer_cov_trace_pc() is not linked in.
35KCOV_INSTRUMENT := n
36
37# Force dependency
38$(obj)/vdso.o : $(obj)/vdso.so
39
40# Link rule for the .so file
41$(obj)/vdso.so.raw: $(obj)/vdso.lds $(obj-vdso) FORCE
42	$(call if_changed,ld)
43
44$(obj)/vdso.so.dbg: $(obj)/vdso.so.raw $(obj)/vdsomunge FORCE
45	$(call if_changed,vdsomunge)
46
47# Strip rule for the .so file
48$(obj)/%.so: OBJCOPYFLAGS := -S
49$(obj)/%.so: $(obj)/%.so.dbg FORCE
50	$(call if_changed,objcopy)
51
52quiet_cmd_vdsomunge = MUNGE   $@
53      cmd_vdsomunge = $(objtree)/$(obj)/vdsomunge $< $@
54
55#
56# Install the unstripped copy of vdso.so.dbg.  If our toolchain
57# supports build-id, install .build-id links as well.
58#
59# Cribbed from arch/x86/vdso/Makefile.
60#
61quiet_cmd_vdso_install = INSTALL $<
62define cmd_vdso_install
63	cp $< "$(MODLIB)/vdso/vdso.so"; \
64	if readelf -n $< | grep -q 'Build ID'; then \
65	  buildid=`readelf -n $< |grep 'Build ID' |sed -e 's/^.*Build ID: \(.*\)$$/\1/'`; \
66	  first=`echo $$buildid | cut -b-2`; \
67	  last=`echo $$buildid | cut -b3-`; \
68	  mkdir -p "$(MODLIB)/vdso/.build-id/$$first"; \
69	  ln -sf "../../vdso.so" "$(MODLIB)/vdso/.build-id/$$first/$$last.debug"; \
70	fi
71endef
72
73$(MODLIB)/vdso: FORCE
74	@mkdir -p $(MODLIB)/vdso
75
76PHONY += vdso_install
77vdso_install: $(obj)/vdso.so.dbg $(MODLIB)/vdso
78	$(call cmd,vdso_install)
79