The kmod test needs the kernel-devsrc package in the SDK. For conventional SDKs this is fine, but for minimal eSDKs we'd usually just devtool sdk-install that recipe, but there is no populate_sysroot task as it's been deleted: Initialising tasks... ERROR: Task do_populate_sysroot does not exist for target kernel-devsrc (/srv/pokybuild/yocto-worker/qemuarm/build/build/tmp/work/qemuarm-poky-linux-gnueabi/core-image-minimal/1.0/testsdkext/layers/build/meta/recipes-kernel/linux/kernel-devsrc.bb:do_populate_sysroot).