> -----Original Message----- > From: Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx> > > On 7/8/22 10:23 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. > > > > Guillaume Tucker (4): > > selftests: drop khdr make target > > selftests: stop using KSFT_KHDR_INSTALL > > selftests: drop KSFT_KHDR_INSTALL make target > > Makefile: add headers_install to kselftest targets > > > > This takes us to back to the state before b2d35fa5fc80 added > khdr support. I reluctantly agreed to the change and it has > proven to be a problematic change. I would rather have had the > dependency stated that headers should be installed prior to > building tests - test build depends on kernel build anyway and > having dependency on headers having build isn't a huge deal. > > So I am in favor of getting rid of khdr support. However, this > khdr support was a change originated from Linaro test ring. Undoing > this might have implication on their workflow. > > I will pull them into the discussion so they are aware of it and > be prepared for this change. I ran into this bug quite a while ago. I reported it here: https://lore.kernel.org/all/ECADFF3FD767C149AD96A924E7EA6EAF977BD214@xxxxxxxxxxxxxxxxxxxxxxx/ it was fixed here: https://lore.kernel.org/all/20191015014505.14259-1-skhan@xxxxxxxxxxxxxxxxxxx/ but apparently reverting it was discussed, based on this: https://lore.kernel.org/all/8d34a9b9-f8f3-0e37-00bf-c342cf3d4074@xxxxxxx/ I'm not sure what happened after that. I was able to work around it by avoiding putting the build directory inside the source tree. I strongly support getting rid of the khdr stuff, as it's quite hard to follow. I think my workflow would not be affected (but I should run off and test it.) Thanks for working on this Guillaume! -- Tim
