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-rw-r--r--arch/arm64/kernel/vdso/Makefile84
1 files changed, 84 insertions, 0 deletions
diff --git a/arch/arm64/kernel/vdso/Makefile b/arch/arm64/kernel/vdso/Makefile
new file mode 100644
index 000000000..d65f52264
--- /dev/null
+++ b/arch/arm64/kernel/vdso/Makefile
@@ -0,0 +1,84 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Building a vDSO image for AArch64.
+#
+# Author: Will Deacon <will.deacon@arm.com>
+# Heavily based on the vDSO Makefiles for other archs.
+#
+
+# Absolute relocation type $(ARCH_REL_TYPE_ABS) needs to be defined before
+# the inclusion of generic Makefile.
+ARCH_REL_TYPE_ABS := R_AARCH64_JUMP_SLOT|R_AARCH64_GLOB_DAT|R_AARCH64_ABS64
+include $(srctree)/lib/vdso/Makefile
+
+obj-vdso := vgettimeofday.o note.o sigreturn.o
+
+# Build rules
+targets := $(obj-vdso) vdso.so vdso.so.dbg
+obj-vdso := $(addprefix $(obj)/, $(obj-vdso))
+
+btildflags-$(CONFIG_ARM64_BTI_KERNEL) += -z force-bti
+
+# -Bsymbolic has been added for consistency with arm, the compat vDSO and
+# potential future proofing if we end up with internal calls to the exported
+# routines, as x86 does (see 6f121e548f83 ("x86, vdso: Reimplement vdso.so
+# preparation in build-time C")).
+ldflags-y := -shared -nostdlib -soname=linux-vdso.so.1 --hash-style=sysv \
+ -Bsymbolic $(call ld-option, --no-eh-frame-hdr) --build-id=sha1 -n \
+ $(btildflags-y) -T
+
+ccflags-y := -fno-common -fno-builtin -fno-stack-protector -ffixed-x18
+ccflags-y += -DDISABLE_BRANCH_PROFILING
+
+CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -Os $(CC_FLAGS_SCS) $(GCC_PLUGINS_CFLAGS)
+KASAN_SANITIZE := n
+UBSAN_SANITIZE := n
+OBJECT_FILES_NON_STANDARD := y
+KCOV_INSTRUMENT := n
+
+CFLAGS_vgettimeofday.o = -O2 -mcmodel=tiny -fasynchronous-unwind-tables
+
+ifneq ($(c-gettimeofday-y),)
+ CFLAGS_vgettimeofday.o += -include $(c-gettimeofday-y)
+endif
+
+# Disable gcov profiling for VDSO code
+GCOV_PROFILE := n
+
+obj-y += vdso.o
+targets += vdso.lds
+CPPFLAGS_vdso.lds += -P -C -U$(ARCH)
+
+# Force dependency (incbin is bad)
+$(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
+ $(call if_changed,vdsold_and_vdso_check)
+
+# Strip rule for the .so file
+$(obj)/%.so: OBJCOPYFLAGS := -S
+$(obj)/%.so: $(obj)/%.so.dbg FORCE
+ $(call if_changed,objcopy)
+
+# Generate VDSO offsets using helper script
+gen-vdsosym := $(srctree)/$(src)/gen_vdso_offsets.sh
+quiet_cmd_vdsosym = VDSOSYM $@
+ cmd_vdsosym = $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@
+
+include/generated/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE
+ $(call if_changed,vdsosym)
+
+# Actual build commands
+quiet_cmd_vdsold_and_vdso_check = LD $@
+ cmd_vdsold_and_vdso_check = $(cmd_ld); $(cmd_vdso_check)
+
+# 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