On Wed, Jun 26, 2019 at 11:30 PM Sam Ravnborg <sam@xxxxxxxxxxxx> wrote: > > On Tue, Jun 25, 2019 at 05:51:27PM +0900, Masahiro Yamada wrote: > > Commit 0126be38d988 ("kbuild: announce removal of SUBDIRS if used") > > added a hint about the 'SUBDIRS' replacement, but it was not clear > > enough. > > > > Multiple people sent me similar questions, patches. > > > > https://lkml.org/lkml/2019/1/17/456 > > > > I did not mean to suggest M= for building a subdirectory in the kernel > > tree. > > > > >From the commit 669efc76b317 ("net: hns3: fix compile error"), people > > already (ab)use M=... to do that because it seems to work to some extent. > > > > Documentation/kbuild/kbuild.txt says M= and KBUILD_EXTMOD are used for > > building external modules. > > > > In fact, Kbuild supports the single target '%/' for this purpose, but > > this may not be noticed much. > > > > Kindly add more hints. > > > > Makefile:213: ================= WARNING ================ > > Makefile:214: 'SUBDIRS' will be removed after Linux 5.3 > > Makefile:215: > > Makefile:216: If you are building an individual subdirectory > > Makefile:217: in the kernel tree, you can do like this: > > Makefile:218: $ make path/to/dir/you/want/to/build/ > > Makefile:219: (Do not forget the trailing slash) > > Makefile:220: > > Makefile:221: If you are building an external module, > > Makefile:222: Please use 'M=' or 'KBUILD_EXTMOD' instead > > Makefile:223: ========================================== > > > > Suggested-by: Christoph Hellwig <hch@xxxxxx> > > Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> > > Nice! > > Acked-by: Sam Ravnborg <sam@xxxxxxxxxxxx> > > Sam Applied to linux-kbuild. -- Best Regards Masahiro Yamada