Yes, it works. Reverted the previous patch and did this:
diff --git a/arch/x86/vdso/Makefile b/arch/x86/vdso/Makefile
index f385a4b..b8bd0c4 100644
--- a/arch/x86/vdso/Makefile
+++ b/arch/x86/vdso/Makefile
@@ -48,7 +48,7 @@ obj-$(VDSO64-y) += vdso-syms.lds
# Match symbols in the DSO that look like VDSO*; produce a file of
constants.
#
sed-vdsosym := -e 's/^00*/0/' \
- -e 's/^\([0-9a-fA-F]*\) . \(VDSO[a-zA-Z0-9_]*\)$$/\2 = 0x\1;/p'
+ -e 's/^\([[:xdigit:]]*\) . \(VDSO[[:alnum:]_]*\)$$/\2 = 0x\1;/p'
quiet_cmd_vdsosym = VDSOSYM $@
cmd_vdsosym = $(NM) $< | sed -n $(sed-vdsosym) | LC_ALL=C sort >
$@
--