Hi. On Mon, Apr 8, 2019 at 5:03 PM Wiebe, Wladislav (Nokia - DE/Ulm) <wladislav.wiebe@xxxxxxxxx> wrote: > > Hi! > > On 07.04.2019 11:04, Masahiro Yamada wrote: > > (+CC Jonas Gorski) > > > > > > On Tue, Mar 26, 2019 at 6:58 PM Wiebe, Wladislav (Nokia - DE/Ulm) > > <wladislav.wiebe@xxxxxxxxx> wrote: > >> > >> Commit ea837f1c0503 ("kbuild: make modpost processing configurable") > >> was intended to give KBUILD_MODPOST_WARN flexibility to be configurable. > >> Right now KBUILD_MODPOST_WARN gets just ignored when KBUILD_EXTMOD is > >> set which happens per default when building modules out of the tree. > >> > >> This change gives the opportunity to define module build behaving also > >> in case of out of tree builds and default will become exit on error. > >> Errors which can be detected by the build should be trapped out of the box > >> there, unless somebody wants to notice broken stuff later at runtime. > > > > If an external module refers to a symbol > > provided by another external module, > > this patch will turn the warning into the error by default, > > which is probably a bad idea. > > Indeed, exactly this should happen. You should fix your external module > dependencies by providing their symbols. Please use e.g. > KBUILD_EXTRA_SYMBOLS instead of converting errors to warning and hoping > that things will work. I know this option. What I want to say is, this patch changes the behavior, and may annoy some people. > Or how do you want to make sure module A still > delivers all symbols needed by module B after an update/changes? > Manually comparing the logs after an update or waiting until it turns > out broken during run-time? I wouldn't say this is a good idea :-) OK, so the commit log should record both the behavior change and workarounds. - If an external module being built refers to symbols in another external module, Kbuild previously showed a warning, but going forward it will turn it into an error. - To work around this, you should pass a symbol table via KBUILD_EXTRA_SYMBOLS, or KBUILD_EXTRA_SYMBOLS=1 to turn the error into a warning. Thanks. > > > I suggested a desired change in the following. > > https://patchwork.kernel.org/patch/9980691/ > > > > I am poking Jonas Gorski > > if he plans to send v2. > > I wouldn't vote for v2 based on explanation above. > > - Wladislav > > > > > > >> Signed-off-by: Wladislav Wiebe <wladislav.wiebe@xxxxxxxxx> > >> --- > >> scripts/Makefile.modpost | 2 +- > >> 1 file changed, 1 insertion(+), 1 deletion(-) > >> > >> diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost > >> index 6b7f354f189a..fec6ec2ffa47 100644 > >> --- a/scripts/Makefile.modpost > >> +++ b/scripts/Makefile.modpost > >> @@ -78,7 +78,7 @@ modpost = scripts/mod/modpost \ > >> $(if $(KBUILD_EXTRA_SYMBOLS), $(patsubst %, -e %,$(KBUILD_EXTRA_SYMBOLS))) \ > >> $(if $(KBUILD_EXTMOD),-o $(modulesymfile)) \ > >> $(if $(CONFIG_SECTION_MISMATCH_WARN_ONLY),,-E) \ > >> - $(if $(KBUILD_EXTMOD)$(KBUILD_MODPOST_WARN),-w) > >> + $(if $(KBUILD_MODPOST_WARN),-w) > >> > >> MODPOST_OPT=$(subst -i,-n,$(filter -i,$(MAKEFLAGS))) > >> > >> -- > >> 2.19.2 > > > > > > -- Best Regards Masahiro Yamada