diff --git a/build/tasks/kernel.mk b/build/tasks/kernel.mk
index 19663c7..a810fd9 100644
--- a/build/tasks/kernel.mk
+++ b/build/tasks/kernel.mk
@@ -288,7 +288,7 @@
 	$(hide) if [ ! -z "$(KERNEL_ADDITIONAL_CONFIG)" ]; then \
 			echo "Using additional config '$(KERNEL_ADDITIONAL_CONFIG)'"; \
 			$(KERNEL_SRC)/scripts/kconfig/merge_config.sh -m -O $(KERNEL_OUT) $(KERNEL_OUT)/.config $(KERNEL_SRC)/arch/$(KERNEL_ARCH)/configs/$(KERNEL_ADDITIONAL_CONFIG); \
-			$(call make-kernel-target,KCONFIG_ALLCONFIG=$(KERNEL_OUT)/.config alldefconfig); \
+			$(call make-kernel-target,KCONFIG_ALLCONFIG=$(KERNEL_BUILD_OUT_PREFIX)$(KERNEL_OUT)/.config alldefconfig); \
 		fi
 
 $(TARGET_PREBUILT_INT_KERNEL): $(KERNEL_CONFIG) $(DEPMOD) $(DTC)