On Fri, May 17, 2019 at 8:33 AM 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> > --- > > Changes in v2: > - redirect messages to stderr > - use '--' after 'basename -a' > - use '-r' for xargs to cope with empty modules.order/modules.builtin > > Makefile | 1 + > scripts/modules-check.sh | 20 ++++++++++++++++++++ > 2 files changed, 21 insertions(+) > create mode 100755 scripts/modules-check.sh > > diff --git a/Makefile b/Makefile > index a61a95b6b38f..30792fec7a12 100644 > --- a/Makefile > +++ b/Makefile > @@ -1290,6 +1290,7 @@ modules: $(vmlinux-dirs) $(if $(KBUILD_BUILTIN),vmlinux) modules.builtin > $(Q)$(AWK) '!x[$$0]++' $(vmlinux-dirs:%=$(objtree)/%/modules.order) > $(objtree)/modules.order > @$(kecho) ' Building modules, stage 2.'; > $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.modpost > + $(Q)$(CONFIG_SHELL) $(srctree)/scripts/modules-check.sh > > modules.builtin: $(vmlinux-dirs:%=%/modules.builtin) > $(Q)$(AWK) '!x[$$0]++' $^ > $(objtree)/modules.builtin > diff --git a/scripts/modules-check.sh b/scripts/modules-check.sh > new file mode 100755 > index 000000000000..c875f6eab01e > --- /dev/null > +++ b/scripts/modules-check.sh > @@ -0,0 +1,20 @@ > +#!/bin/sh > +# SPDX-License-Identifier: GPL-2.0 > + > +set -e > + > +# Check uniqueness of module names > +check_same_name_modules() > +{ > + same_name_modules=$(cat modules.order modules.builtin | \ > + xargs -r basename -a -- | sort | uniq -d) > + > + for m in $same_name_modules > + do > + echo "warning: same basename if the following are built as modules:" >&2 > + grep -h -e "/$m" modules.order modules.builtin | \ > + sed 's:^kernel/: :' >&2 > + done > +} > + > +check_same_name_modules > -- > 2.17.1 > The 'xargs' '-r' flag is a GNU extension. If POSIX compliance is important here, the use of 'cat', 'xargs' and 'basename' may be substituted with that of 'sed' to initialise same_name_modules: sed 's!.*/!!' modules.order modules.builtin | sort | uniq -d 'Sed' may also be used on its own in the 'for' loop instead of as part of a pipeline along with 'grep' to generate the desired output: sed '/\/'$m'/!d;s:^kernel/: :' modules.order modules.builtin Just a suggestion.