On 7/12/22 2:29 AM, Guillaume Tucker wrote:
Earlier attempts to get "make O=build kselftest-all" to work were not successful as they made undesirable changes to some functions in the top-level Makefile. This series takes a different approach by removing the root cause of the problem within kselftest, which is when the sub-Makefile tries to install kernel headers "backwards" by calling make with the top-level Makefile. The actual issue comes from the fact that $(srctree) is ".." when building in a sub-directory with "O=build" which then obviously makes "-C $(top_srcdir)" point outside of the real source tree.
With this series, the generic kselftest targets work as expected from the top level with or without a build directory e.g.:
$ make kselftest-all
$ make O=build kselftest-all
Then in order to build using the sub-Makefile explicitly, the headers have to be installed first. This is arguably a valid requirement to have when building a tool from a sub-Makefile. For example, "make -C tools/testing/nvdimm/" fails in a similar way until <asm/rwonce.h> has been generated by a kernel build.
v2: replace headers_install with headers
I already applied the series. Please send me patches I can apply on top of the ones in linux-kselftest next branch.
thanks, -- Shuah