[PATCH v2 3/3] tile: thin archives fix linking

[Nicholas Piggin <npiggin@gmail.com>]

The VDSO symbols can't be linked into built-in.o when building with
thin archives, so change this to linking a new object file that is
included into the built-in.o.

Cc: Chris Metcalf <cmetcalf@mellanox.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/tile/kernel/vdso/Makefile | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/arch/tile/kernel/vdso/Makefile b/arch/tile/kernel/vdso/Makefile
index c54fff37b5ff..e140472d5be6 100644
--- a/arch/tile/kernel/vdso/Makefile
+++ b/arch/tile/kernel/vdso/Makefile
@@ -11,7 +11,7 @@ obj-vdso := $(addprefix $(obj)/, $(obj-vdso))
 # vdso32 is only for tilegx -m32 compat task.
 VDSO32-$(CONFIG_COMPAT) := y
 
-obj-y += vdso.o
+obj-y += vdso.o vdso-syms.o
 obj-$(VDSO32-y) += vdso32.o
 extra-y += vdso.lds
 CPPFLAGS_vdso.lds += -P -C -U$(ARCH)
@@ -49,16 +49,18 @@ $(obj)/vdso.so.dbg: $(src)/vdso.lds $(obj-vdso)
 # We also create a special relocatable object that should mirror the symbol
 # table and layout of the linked DSO.  With ld -R we can then refer to
 # these symbols in the kernel code rather than hand-coded addresses.
-extra-y += vdso-syms.o
-$(obj)/built-in.o: $(obj)/vdso-syms.o
-$(obj)/built-in.o: ld_flags += -R $(obj)/vdso-syms.o
 
 SYSCFLAGS_vdso.so.dbg = -shared -s -Wl,-soname=linux-vdso.so.1 \
                             $(call cc-ldoption, -Wl$(comma)--hash-style=both)
-SYSCFLAGS_vdso_syms.o = -r
-$(obj)/vdso-syms.o: $(src)/vdso.lds $(obj)/vrt_sigreturn.o FORCE
+SYSCFLAGS_vdso_dummy.o = -r
+$(obj)/vdso-dummy.o: $(src)/vdso.lds $(obj)/vrt_sigreturn.o FORCE
 	$(call if_changed,vdsold)
 
+quiet_cmd_vdso_sym = VDSOSYM $@
+      cmd_vdso_sym = $(LD) -r -R $(obj)/vdso-dummy.o -o $@
+
+$(obj)/vdso-syms.o: $(obj)/vdso-dummy.o
+	$(call if_changed,vdso_sym)
 
 # strip rule for the .so file
 $(obj)/%.so: OBJCOPYFLAGS := -S
-- 
2.11.0