diff --git a/tools/bpf/bpftool/Makefile b/tools/bpf/bpftool/Makefile
index 892dbf095bff..0911b00b25cc 100644
--- a/tools/bpf/bpftool/Makefile
+++ b/tools/bpf/bpftool/Makefile
@@ -23,7 +23,7 @@ endif
 
 LIBBPF = $(BPF_PATH)libbpf.a
 
-BPFTOOL_VERSION=$(shell make --no-print-directory -sC ../../.. kernelversion)
+BPFTOOL_VERSION := $(shell make --no-print-directory -sC ../../.. kernelversion)
 
 $(LIBBPF): FORCE
 	$(Q)$(MAKE) -C $(BPF_DIR) OUTPUT=$(OUTPUT) $(OUTPUT)libbpf.a FEATURES_DUMP=$(FEATURE_DUMP_EXPORT)