On Fri, May 1, 2020 at 4:25 AM Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx> wrote: > > A new behavior on more recent kernels require to always call > "make modules_prepare" after *any* Kconfig changes. Again, this is the behavior since 2004. This commit: https://git.kernel.org/pub/scm/linux/kernel/git/history/history.git/commit/?id=95065ad3fa787c417008a36d3a5d9a3bab17ab98 Shrug if you complain about what has been stable more than 15 years. > This is not what a poor mortal would be expecting on a building > system, as it should, IMHO, be able to detect and auto-run > whatever is needed to use the newer setup. No. External module builds should never ever attempt to update in-tree files. This is because the build environment for external modules is usually located in /lib/modules/$(uname -r)/build/, which is read-only. A number of upstream developers (ab)use M= to compile test individual directories, despite the fact Kbuild supports the single target 'make drivers/staging/media/stomisp/' You need to cope with this conflicting comment line: https://github.com/masahir0y/linux/blob/v5.6/Makefile#L681 since you care if auto.conf is up-to-date. > Yet, while this is not solved, let's at least stop the build > and produce a warning, to notify the user about that. > > Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx> > --- > > I would still prefer to call "make modules_prepare" directly, > on such cases, but just calling "make -C . modules_prepare" doesn't > work. So, the next best thing would be to at least print a message > and don't try to do a build with a broken auto.conf file. > > Makefile | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/Makefile b/Makefile > index 70def4907036..492ee2396ab9 100644 > --- a/Makefile > +++ b/Makefile > @@ -1632,6 +1632,11 @@ $(objtree)/Module.symvers: > build-dirs := $(KBUILD_EXTMOD) > PHONY += modules > modules: descend $(objtree)/Module.symvers > + @if [ $(KCONFIG_CONFIG) -nt include/config/auto.conf ]; then \ > + echo " WARNING: $(KCONFIG_CONFIG) was modified. Need to run:"; \ > + echo " $(MAKE) modules_prepare"; \ > + exit -1; \ > + fi > $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost > > PHONY += modules_install -- Best Regards Masahiro Yamada
