On Tue, Apr 9, 2019 at 7:31 PM Jonas Gorski <jonas.gorski@xxxxxxxxx> wrote: > > Hi, > > 本当に申し訳ありません, I got sidetracked and completely forgot about it. I > actually still have my old tree with the suggested changes for v2. > > On Tue, 9 Apr 2019 at 11:01, Masahiro Yamada > <yamada.masahiro@xxxxxxxxxxxxx> wrote: > > > > 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. > > This sounds like a good middle ground. When you do the effort of > setting KBUILD_EXTRA_SYMBOLS, you are likely interested in proper > dependency resolution and being notified if it fails. > > I would probably still use KBUILD_MODPOST_WARN=0 to force the warnings > as errors, to have it as the central switch for the behaviour. So the > behaviour would then become > > - If KBUILD_MODPOST_WARN is set to any value, set -w accordingly > - else, set -w only when building for an external module and > KBUILD_EXTRA_SYMBOLS is empty > > or > > ifdef KBUILD_MODPOST_WARN > KBUILD_MODPOST_WARN:=$(filter-out 0,$(KBUILD_MODPOST_WARN)) > else > KBUILD_MODPOST_WARN:=$(if $(KBUILD_EXTMOD),$(if $(KBUILD_EXTRA_SYMBOLS),,1)) > endif Sorry, I think this is too complicated. I applied this since it is simple. https://patchwork.kernel.org/patch/10895465/ -- Best Regards Masahiro Yamada