Re: [PATCH v4 2/3] tools build: Avoid circular .fixdep-in.o.cmd issues

Thorsten Leemhuis
2024-08-12T06:32:46Z

On 15.07.24 22:32, Brian Norris wrote:
> The 'fixdep' tool is used to post-process dependency files for various
> reasons, and it runs after every object file generation command. This
> even includes 'fixdep' itself.

Lo! TWIMC, this change broke my daily arm64 and x86_64 Fedora vanilla RPM
builds on all Fedora releases when it hit -next a few days ago. Reverting
it fixes the problem.

The problem is related to the RPM magic somehow, as building worked fine
when when I omitted stuff like "-specs=/usr/lib/rpm/redhat/redhat-
hardened-cc1 -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1" from the
make call. So the real problem might be that space somewhere.

This is how the build fails on x86_64:

+ /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 ' '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 ' ARCH=x86_64 'KCFLAGS= ' WITH_GCOV=0 -j2 bzImage
/usr/bin/ld: /tmp/ccMoR0Wr.o: relocation R_X86_64_32 against `.rodata' can not be used when making a PIE object; recompile with -fPIE
/usr/bin/ld: failed to set dynamic section sizes: bad value
collect2: error: ld returned 1 exit status
make[4]: *** [Makefile:47: /builddir/build/BUILD/kernel-next-20240812/linux-6.11.0-0.0.next.20240812.329.vanilla.fc40.x86_64/tools/objtool/fixdep] Error 1
make[3]: *** [/builddir/build/BUILD/kernel-next-20240812/linux-6.11.0-0.0.next.20240812.329.vanilla.fc40.x86_64/tools/build/Makefile.include:15: fixdep] Error 2
make[2]: *** [Makefile:73: objtool] Error 2
make[1]: *** [/builddir/build/BUILD/kernel-next-20240812/linux-6.11.0-0.0.next.20240812.329.vanilla.fc40.x86_64/Makefile:1361: tools/objtool] Error 2
make[1]: *** Waiting for unfinished jobs....
make: *** [Makefile:226: __sub-make] Error 2
error: Bad exit status from /var/tmp/rpm-tmp.ZQfBFY (%build)

This is how it fails on arm64:

+ /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 -mbranch-protection=standard -fasynchronous-unwind-tables -fstack-clash-protection ' 'HOSTLDFLAGS=-Wl,-z,relro -Wl,--as-needed -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 ' ARCH=arm64 'KCFLAGS= ' WITH_GCOV=0 -j4 vmlinuz.efi
/usr/bin/ld: /tmp/ccRCv9ot.o: relocation R_AARCH64_ADR_PREL_PG_HI21 against symbol `stderr@@GLIBC_2.17' which may bind externally can not be used when making a shared object; recompile with -fPIC
/usr/bin/ld: /tmp/ccRCv9ot.o(.text+0x8): unresolvable R_AARCH64_ADR_PREL_PG_HI21 relocation against symbol `stderr@@GLIBC_2.17'
/usr/bin/ld: final link failed: bad value
collect2: error: ld returned 1 exit status
make[4]: *** [Makefile:47: /builddir/build/BUILD/kernel-next-20240812/linux-6.11.0-0.0.next.20240812.329.vanilla.fc40.aarch64/tools/bpf/resolve_btfids/fixdep] Error 1
make[3]: *** [/builddir/build/BUILD/kernel-next-20240812/linux-6.11.0-0.0.next.20240812.329.vanilla.fc40.aarch64/tools/build/Makefile.include:15: fixdep] Error 2
make[2]: *** [Makefile:76: bpf/resolve_btfids] Error 2
make[1]: *** [/builddir/build/BUILD/kernel-next-20240812/linux-6.11.0-0.0.next.20240812.329.vanilla.fc40.aarch64/Makefile:1362: tools/bpf/resolve_btfids] Error 2
make[1]: *** Waiting for unfinished jobs....
make: *** [Makefile:226: __sub-make] Error 2
error: Bad exit status from /var/tmp/rpm-tmp.60qjsr (%build)

Full logs:
https://download.copr.fedorainfracloud.org/results/@kernel-vanilla/next/fedora-40-x86_64/07900504-next-next-all/builder-live.log.gz
https://download.copr.fedorainfracloud.org/results/@kernel-vanilla/next/fedora-40-aarch64/07900504-next-next-all/builder-live.log.gz

My ppc64le builds worked fine.

Ciao, Thorsten

> In Kbuild, this isn't actually a problem, because it uses a single
> command to generate fixdep (a compile-and-link command on fixdep.c), and
> afterward runs the fixdep command on the accompanying .fixdep.cmd file.
>
> In tools/ builds (which notably is maintained separately from Kbuild),
> fixdep is generated in several phases:
>
> 1. fixdep.c -> fixdep-in.o
> 2. fixdep-in.o -> fixdep
>
> Thus, fixdep is not available in the post-processing for step 1, and
> instead, we generate .cmd files that look like:
>
> ## from tools/objtool/libsubcmd/.fixdep.o.cmd
> # cannot find fixdep (/path/to/linux/tools/objtool/libsubcmd//fixdep)
> [...]
>
> These invalid .cmd files are benign in some respects, but cause problems
> in others (such as the linked reports).
>
> Because the tools/ build system is rather complicated in its own right
> (and pointedly different than Kbuild), I choose to simply open-code the
> rule for building fixdep, and avoid the recursive-make indirection that
> produces the problem in the first place.
>
> Link: https://lore.kernel.org/all/Zk-C5Eg84yt6_nml@google.com/
> Signed-off-by: Brian Norris <briannorris@chromium.org>
> ---
>
> (no changes since v3)
>
> Changes in v3:
> - Drop unnecessary tools/build/Build
>
> tools/build/Build | 3 ---
> tools/build/Makefile | 11 ++---------
> 2 files changed, 2 insertions(+), 12 deletions(-)
> delete mode 100644 tools/build/Build
>
> diff --git a/tools/build/Build b/tools/build/Build
> deleted file mode 100644
> index 76d1a4960973..000000000000
> --- a/tools/build/Build
> +++ /dev/null
> @@ -1,3 +0,0 @@
> -hostprogs := fixdep
> -
> -fixdep-y := fixdep.o
> diff --git a/tools/build/Makefile b/tools/build/Makefile
> index 17cdf01e29a0..fea3cf647f5b 100644
> --- a/tools/build/Makefile
> +++ b/tools/build/Makefile
> @@ -43,12 +43,5 @@ ifneq ($(wildcard $(TMP_O)),)
> $(Q)$(MAKE) -C feature OUTPUT=$(TMP_O) clean >/dev/null
> endif
>
> -$(OUTPUT)fixdep-in.o: FORCE
> - $(Q)$(MAKE) $(build)=fixdep
> -
> -$(OUTPUT)fixdep: $(OUTPUT)fixdep-in.o
> - $(QUIET_LINK)$(HOSTCC) $(KBUILD_HOSTLDFLAGS) -o $@ $<
> -
> -FORCE:
> -
> -.PHONY: FORCE
> +$(OUTPUT)fixdep: $(srctree)/tools/build/fixdep.c
> + $(QUIET_CC)$(HOSTCC) $(KBUILD_HOSTLDFLAGS) -o $@ $<