diff --git a/common.mk b/common.mk
index 206bfa4..320a132 100644
--- a/common.mk
+++ b/common.mk
@@ -124,10 +124,8 @@
 export SRC ?= $(CURDIR)
 
 # If BASE_VER is not set, read the libchrome revision number from
-# common-mk/BASE_VER file.
-ifeq ($(strip $(BASE_VER)),)
-BASE_VER := $(shell cat $(SRC)/../common-mk/BASE_VER)
-endif
+# /usr/share/libchrome/BASE_VER.
+BASE_VER := $(shell cat $(SYSROOT)/usr/share/libchrome/BASE_VER)
 $(info Using BASE_VER=$(BASE_VER))
 
 # Re-start in the $(OUT) directory if we're not there.