On Fri, May 17, 2019 at 2:46 PM Lucas De Marchi <lucas.de.marchi@xxxxxxxxx> wrote: > > On Thu, May 16, 2019 at 10:37 PM Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > > > > On Fri, May 17, 2019 at 01:45:11PM +0900, Masahiro Yamada wrote: > > > On Fri, May 17, 2019 at 1:29 PM Masahiro Yamada > > > <yamada.masahiro@xxxxxxxxxxxxx> wrote: > > > > > > > > In the recent build test of linux-next, Stephen saw a build error > > > > caused by a broken .tmp_versions/*.mod file: > > > > > > > > https://lkml.org/lkml/2019/5/13/991 > > > > > > > > drivers/net/phy/asix.ko and drivers/net/usb/asix.ko have the same > > > > basename, and there is a race in generating .tmp_versions/asix.mod > > > > > > > > Kbuild has not checked this before, and it suddenly shows up with > > > > obscure error message when this kind of race occurs. > > > > > > > > Non-unique module names cause various sort of problems, but it is > > > > not trivial to catch them by eyes. > > > > > > > > Hence, this script. > > > > > > > > It checks not only real modules, but also built-in modules (i.e. > > > > controlled by tristate CONFIG option, but currently compiled with =y). > > > > Non-unique names for built-in modules also cause problems because > > > > /sys/modules/ would fall over. > > > > > > > > I tested allmodconfig on the latest kernel, and it detected the > > > > following: > > > > > > > > warning: same basename if the following are built as modules: > > > > drivers/regulator/88pm800.ko > > > > drivers/mfd/88pm800.ko > > > > warning: same basename if the following are built as modules: > > > > drivers/gpu/drm/bridge/adv7511/adv7511.ko > > > > drivers/media/i2c/adv7511.ko > > > > warning: same basename if the following are built as modules: > > > > drivers/net/phy/asix.ko > > > > drivers/net/usb/asix.ko > > > > warning: same basename if the following are built as modules: > > > > fs/coda/coda.ko > > > > drivers/media/platform/coda/coda.ko > > > > warning: same basename if the following are built as modules: > > > > drivers/net/phy/realtek.ko > > > > drivers/net/dsa/realtek.ko > > > > > > > > Reported-by: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx> > > > > Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> > > > > Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx> > > > > --- > > > > > > > > > One more question popped up. > > > > > > External modules are out of scope of the community, > > > but it is possible that people create an external module > > > that happens to have the same name as an upstream driver. > > > > That is their bug, nothing we can do about that :) > > It's actually not a bug. For external modules it works pretty much as > intended. See DEPMOD.D(5): the search directive tells what's the > preference among the directories for modules with the same name. > depmod respects that order and put the right one into your > modules.dep. > > This allows to put external modules in a different dir and also to > make backports of modules from recent to ancient kernels. These > modules with the same name are usually the same module, with a > different version. Of course what we have here and you are fixing is a > different story. OK, so external modules should not be checked. Thanks for the explanation! > Reviewed-by: Lucas De Marchi <lucas.demarchi@xxxxxxxxx> > > > Lucas De Marchi -- Best Regards Masahiro Yamada
