x86, relocs: Build separate 32/64-bit tools

Since the ELF structures and access macros change size based on 32 vs
64 bits, build a separate 32-bit relocs tool (for handling realmode
and 32-bit relocations), and a 64-bit relocs tool (for handling 64-bit
kernel relocations).
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: http://lkml.kernel.org/r/1365797627-20874-5-git-send-email-keescook@chromium.orgSigned-off-by: H. Peter Anvin <hpa@linux.intel.com>

arch/x86/boot/compressed/Makefile

@@ -44,7 +44,7 @@ $(obj)/vmlinux.bin: vmlinux FORCE
 
 targets += $(patsubst $(obj)/%,%,$(VMLINUX_OBJS)) vmlinux.bin.all vmlinux.relocs
 
-CMD_RELOCS = arch/x86/tools/relocs
+CMD_RELOCS = arch/x86/tools/relocs_$(BITS)
 quiet_cmd_relocs = RELOCS  $@
       cmd_relocs = $(CMD_RELOCS) $< > $@;$(CMD_RELOCS) --abs-relocs $<
 $(obj)/vmlinux.relocs: vmlinux FORCE

arch/x86/realmode/rm/Makefile

@@ -56,7 +56,7 @@ $(obj)/realmode.bin: $(obj)/realmode.elf $(obj)/realmode.relocs
 	$(call if_changed,objcopy)
 
 quiet_cmd_relocs = RELOCS  $@
-      cmd_relocs = arch/x86/tools/relocs --realmode $< > $@
+      cmd_relocs = arch/x86/tools/relocs_32 --realmode $< > $@
 
 targets += realmode.relocs
 $(obj)/realmode.relocs: $(obj)/realmode.elf FORCE

arch/x86/tools/.gitignore

-relocs
+relocs_32*
+relocs_64*

arch/x86/tools/Makefile

@@ -37,6 +37,22 @@ $(obj)/test_get_len.o: $(srctree)/arch/x86/lib/insn.c $(srctree)/arch/x86/lib/in
 
 $(obj)/insn_sanity.o: $(srctree)/arch/x86/lib/insn.c $(srctree)/arch/x86/lib/inat.c $(srctree)/arch/x86/include/asm/inat_types.h $(srctree)/arch/x86/include/asm/inat.h $(srctree)/arch/x86/include/asm/insn.h $(objtree)/arch/x86/lib/inat-tables.c
 
+HOSTCFLAGS_relocs_32.o += -DELF_BITS=32
+HOSTCFLAGS_relocs_64.o += -DELF_BITS=64
+
+quiet_cmd_cp_reloc = GEN     $@
+      cmd_cp_reloc = cp $< $@
+
+$(obj)/relocs_%.c: $(srctree)/arch/x86/tools/relocs.c
+	$(call cmd,cp_reloc)
+
 HOST_EXTRACFLAGS += -I$(srctree)/tools/include
-hostprogs-y	+= relocs
-relocs: $(obj)/relocs
+hostprogs-y    += relocs_$(BITS)
+relocs_binaries = relocs_$(BITS)
+ifeq ($(CONFIG_64BIT),y)
+	hostprogs-y  += relocs_32
+	relocs_binaries += relocs_32
+endif
+relocs: $(relocs_binaries)
+relocs_32: $(obj)/relocs_32
+relocs_64: $(obj)/relocs_64