diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index 729b4255343a2f484902b9b0fa3a4115f8b447b6..db52c29b073cdcd9d7d12be5b9d28e64b6266fdf 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -116,6 +116,16 @@ INCLUDE_DIR := $(SCRATCH_DIR)/include
 BPFOBJ := $(BUILD_DIR)/libbpf/libbpf.a
 RESOLVE_BTFIDS := $(BUILD_DIR)/resolve_btfids/resolve_btfids
 
+VMLINUX_BTF_PATHS ?= $(if $(O),$(O)/vmlinux)				\
+		     $(if $(KBUILD_OUTPUT),$(KBUILD_OUTPUT)/vmlinux)	\
+		     ../../../../vmlinux				\
+		     /sys/kernel/btf/vmlinux				\
+		     /boot/vmlinux-$(shell uname -r)
+VMLINUX_BTF ?= $(abspath $(firstword $(wildcard $(VMLINUX_BTF_PATHS))))
+ifeq ($(VMLINUX_BTF),)
+$(error Cannot find a vmlinux for VMLINUX_BTF at any of "$(VMLINUX_BTF_PATHS)")
+endif
+
 # Define simple and short `make test_progs`, `make test_sysctl`, etc targets
 # to build individual tests.
 # NOTE: Semicolon at the end is critical to override lib.mk's default static
@@ -140,6 +150,7 @@ $(OUTPUT)/urandom_read: urandom_read.c
 
 $(OUTPUT)/bpf_testmod.ko: $(VMLINUX_BTF) $(wildcard bpf_testmod/Makefile bpf_testmod/*.[ch])
 	$(call msg,MOD,,$@)
+	$(Q)$(RM) bpf_testmod/bpf_testmod.ko # force re-compilation
 	$(Q)$(MAKE) $(submake_extras) -C bpf_testmod
 	$(Q)cp bpf_testmod/bpf_testmod.ko $@
 
@@ -147,16 +158,6 @@ $(OUTPUT)/test_stub.o: test_stub.c $(BPFOBJ)
 	$(call msg,CC,,$@)
 	$(Q)$(CC) -c $(CFLAGS) -o $@ $<
 
-VMLINUX_BTF_PATHS ?= $(if $(O),$(O)/vmlinux)				\
-		     $(if $(KBUILD_OUTPUT),$(KBUILD_OUTPUT)/vmlinux)	\
-		     ../../../../vmlinux				\
-		     /sys/kernel/btf/vmlinux				\
-		     /boot/vmlinux-$(shell uname -r)
-VMLINUX_BTF ?= $(abspath $(firstword $(wildcard $(VMLINUX_BTF_PATHS))))
-ifeq ($(VMLINUX_BTF),)
-$(error Cannot find a vmlinux for VMLINUX_BTF at any of "$(VMLINUX_BTF_PATHS)")
-endif
-
 DEFAULT_BPFTOOL := $(SCRATCH_DIR)/sbin/bpftool
 
 $(OUTPUT)/runqslower: $(BPFOBJ) | $(DEFAULT_BPFTOOL)