LINUX_HEADERS_VERSION = $(call qstrip,$(BR2_DEFAULT_KERNEL_HEADERS))
ifeq ($(findstring x2.6.,x$(LINUX_HEADERS_VERSION)),x2.6.)
LINUX_HEADERS_SITE = $(BR2_KERNEL_MIRROR)/linux/kernel/v2.6
-else
+else ifeq ($(findstring x3.,x$(LINUX_HEADERS_VERSION)),x3.)
LINUX_HEADERS_SITE = $(BR2_KERNEL_MIRROR)/linux/kernel/v3.x
+else ifeq ($(findstring x4.,x$(LINUX_HEADERS_VERSION)),x4.)
+LINUX_HEADERS_SITE = $(BR2_KERNEL_MIRROR)/linux/kernel/v4.x
endif
LINUX_HEADERS_SOURCE = linux-$(LINUX_HEADERS_VERSION).tar.xz