When CONFIG_TRIM_UNUSED_KSYMS=y and CONFIG_BUILD_DOCSRC=y it is possible to get the following error: ERROR: "cn_del_callback" [Documentation/connector/cn_test.ko] undefined! ERROR: "cn_add_callback" [Documentation/connector/cn_test.ko] undefined! ERROR: "cn_netlink_send" [Documentation/connector/cn_test.ko] undefined! ../scripts/Makefile.modpost:91: recipe for target '__modpost' failed It is not sufficient to do "vmlinux-dirs += Documentation" as this also depends on the headers_check target, and all of this needs to be done before adjust_autoksyms.sh is executed. Let's sort this out by gathering those sequential prerequisites in a make target of their own, separate from the vmlinux target. And by doing so, the special autoksyms_recursive target is no longer needed. Signed-off-by: Nicolas Pitre <nico@linaro.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> Tested-by: Randy Dunlap <rdunlap@infradead.org>