x86: insn decoder test checks objdump version

Check objdump version before using it for insn decoder build test,
because some older objdump can't decode AVX code correctly.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: Jim Keniston <jkenisto@us.ibm.com>
LKML-Reference: <20091120171314.6715.30390.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
diff --git a/arch/x86/tools/Makefile b/arch/x86/tools/Makefile
index c80b079..f820826 100644
--- a/arch/x86/tools/Makefile
+++ b/arch/x86/tools/Makefile
@@ -12,8 +12,11 @@
   posttest_64bit = -n
 endif
 
+distill_awk = $(srctree)/arch/x86/tools/distill.awk
+chkobjdump = $(srctree)/arch/x86/tools/chkobjdump.awk
+
 quiet_cmd_posttest = TEST    $@
-      cmd_posttest = $(OBJDUMP) -d -j .text $(objtree)/vmlinux | $(AWK) -f $(srctree)/arch/x86/tools/distill.awk | $(obj)/test_get_len $(posttest_64bit) $(posttest_verbose)
+      cmd_posttest = ($(OBJDUMP) -v | $(AWK) -f $(chkobjdump)) || $(OBJDUMP) -d -j .text $(objtree)/vmlinux | $(AWK) -f $(distill_awk) | $(obj)/test_get_len $(posttest_64bit) $(posttest_verbose)
 
 posttest: $(obj)/test_get_len vmlinux
 	$(call cmd,posttest)