Re: -next build error due to "kbuild: Leave objtool binary around with 'make clean'"

[Nathan Chancellor <nathan@kernel.org>]

On Mon, Mar 02, 2026 at 08:43:57PM +0100, Michal Suchánek wrote:
> On Mon, Mar 02, 2026 at 08:18:17PM +0100, Thorsten Leemhuis wrote:
> > On 2/28/26 06:40, Nathan Chancellor wrote:
> > > The difference between 'make clean' and 'make mrproper' is documented in
> > > 'make help' as:
> > > 
> > >   clean     - Remove most generated files but keep the config and
> > >               enough build support to build external modules
> > >   mrproper  - Remove all generated files + config + various backup files
> > > 
> > > After commit 68b4fe32d737 ("kbuild: Add objtool to top-level clean
> > > target"), running 'make clean' then attempting to build an external
> > > module with the resulting build directory fails with
> > > 
> > >   $ make ARCH=x86_64 O=build clean
> > > 
> > >   $ make -C build M=... MO=...
> > >   ...
> > >   /bin/sh: line 1: .../build/tools/objtool/objtool: No such file or directory
> > > 
> > > as 'make clean' removes the objtool binary.
> > > 
> > > Split the objtool clean target into mrproper and clean like Kbuild does
> > > and remove all generated artifacts with 'make clean' except for the
> > > objtool binary, which is removed with 'make mrproper'.
> > 
> > Thx for fixing this regression, sadly this caused my daily -next rpm
> > builds for Fedora to fail on x86_64 during a "make mrproper":
> > 
> > ""
> > kernel.spec:2485: InitBuildVars: Copy files
> > + /usr/bin/make -s 'HOSTCFLAGS=-O2  -fexceptions -g -grecord-gcc-switches -pipe -Wall -Werror=format-security -Wp,-U_FORTIFY_SOURCE,-D_FORTIFY_SOURCE=3 -Wp,-D_GLIBCXX_ASSERTIONS -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -fstack-protector-strong -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1  -m64 -march=x86-64 -mtune=generic -fasynchronous-unwind-tables -fstack-clash-protection -fcf-protection -mtls-dialect=gnu2   ' 'HOSTLDFLAGS=-Wl,-z,relro -Wl,--as-needed  -Wl,-z,pack-relative-relocs -Wl,-z,now -specs=/usr/lib/rpm/redhat/redhat-hardened-ld -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1  -Wl,--build-id=sha1 -specs=/usr/lib/rpm/redhat/redhat-package-notes ' -j32 mrproper
> > find: cannot delete ‘/builddir/build/BUILD/kernel-7.0.0-build/kernel-next-20260302/linux-7.0.0-0.0.next.20260302.121.vanilla.fc42.x86_64/tools/objtool/.check.o.cmd’: No such file or directory
> > find: cannot delete ‘/builddir/build/BUILD/kernel-7.0.0-build/kernel-next-20260302/linux-7.0.0-0.0.next.20260302.121.vanilla.fc42.x86_64/tools/objtool/.elf.o.cmd’: No such file or directory
> > [and many more like these]
> > ""
> > For the full build log, see:
> > https://download.copr.fedorainfracloud.org/results/@kernel-vanilla/next/fedora-42-x86_64/10183736-next-next-all/builder-live.log.gz
> > 
> > This is almost exactly the rpm spec file that is used in Fedora rawhide.
> > The sections that causes this looks like this:
> > 
> > """
> >     %{log_msg "InitBuildVars: Copy files"}
> >     %{make} %{?_smp_mflags} mrproper
...
> Or does the objtool_clean run multiple times in parallel, once through
> the clean target, and once as dependency of the mrproper target?

More than likely this based on my reading of the submake processes from
the build log. For what it's worth, I cannot reproduce this error on
either a really fast or really slow build machine but it should not be
hard to avoid by using 'xargs rm -f' like the rest of Kbuild does for
removing things, which should suppress the error if the file does not
exist. Thorsten, could you see if this diff makes a difference for you?
If so, I'll squash it in with a note.

diff --git a/tools/objtool/Makefile b/tools/objtool/Makefile
index 50d3e38e6137..76bcd4e85de3 100644
--- a/tools/objtool/Makefile
+++ b/tools/objtool/Makefile
@@ -142,7 +142,7 @@ $(LIBSUBCMD)-clean:
 	$(Q)$(RM) -r -- $(LIBSUBCMD_OUTPUT)
 
 clean: $(LIBSUBCMD)-clean
-	$(Q)find $(OUTPUT) -name '*.o' -delete -o -name '\.*.cmd' -delete -o -name '\.*.d' -delete
+	$(Q)find $(OUTPUT) \( -name '*.o' -o -name '\.*.cmd' -o -name '\.*.d' \) -type f -print | xargs $(RM)
 	$(Q)$(RM) $(OUTPUT)arch/x86/lib/cpu-feature-names.c $(OUTPUT)fixdep
 	$(Q)$(RM) $(OUTPUT)arch/x86/lib/inat-tables.c $(OUTPUT)fixdep
 	$(Q)$(RM) -- $(OUTPUT)FEATURE-DUMP.objtool