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References: <20230119082250.151485-1-masahiroy@kernel.org> <CACPK8XeGsWN+2L57=dfQWOTSo8df7_qrxhwvV4Ho0rkhV=0vSw@mail.gmail.com>
In-Reply-To: <CACPK8XeGsWN+2L57=dfQWOTSo8df7_qrxhwvV4Ho0rkhV=0vSw@mail.gmail.com>
From:   Masahiro Yamada <masahiroy@kernel.org>
Date:   Thu, 19 Jan 2023 21:37:57 +0900
Message-ID: <CAK7LNAQWtDHOs=K+qznt5U1WiDv86tChkj4zOer4wtVRB974OA@mail.gmail.com>
Subject: Re: [PATCH] powerpc: remove checks for binutils older than 2.25
To:     Joel Stanley <joel@jms.id.au>
Cc:     linux-kbuild@vger.kernel.org,
        Michael Ellerman <mpe@ellerman.id.au>,
        Nicholas Piggin <npiggin@gmail.com>,
        Christophe Leroy <christophe.leroy@csgroup.eu>,
        linuxppc-dev@lists.ozlabs.org,
        Nathan Chancellor <nathan@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        linux-kernel@vger.kernel.org, Nicolas Schier <nicolas@fjasle.eu>
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On Thu, Jan 19, 2023 at 9:12 PM Joel Stanley <joel@jms.id.au> wrote:
>
> On Thu, 19 Jan 2023 at 08:24, Masahiro Yamada <masahiroy@kernel.org> wrote:
> >
> > Commit e4412739472b ("Documentation: raise minimum supported version of
> > binutils to 2.25") allows us to remove the checks for old binutils.
> >
> > There is no more user for ld-ifversion. Remove it as well.
>
> ppc kernels fail to link with 2.27 under some configurations:
>
>  https://github.com/linuxppc/issues/issues/388
>
> We may want to use ld-ifversion to exclude that version.


For LLD, CONFIG option is directly checked.


masahiro@zoe:~/ref/linux(master)$ git grep  CONFIG_LLD_VERSION
Makefile:ifeq ($(call test-lt, $(CONFIG_LLD_VERSION), 130000),y)
arch/riscv/Makefile:ifeq ($(call test-lt, $(CONFIG_LLD_VERSION), 150000),y)
arch/x86/Makefile:ifeq ($(call test-lt, $(CONFIG_LLD_VERSION), 130000),y)
scripts/Kbuild.include:# Usage: $(call test-lt, $(CONFIG_LLD_VERSION), 150000)


> >
> > Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
> > ---
> >
> >  arch/powerpc/Makefile     | 22 +---------------------
> >  arch/powerpc/lib/Makefile |  2 +-
> >  scripts/Makefile.compiler |  4 ----
> >  3 files changed, 2 insertions(+), 26 deletions(-)
> >
> > diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile
> > index dc4cbf0a5ca9..3d265b16c0ae 100644
> > --- a/arch/powerpc/Makefile
> > +++ b/arch/powerpc/Makefile
> > @@ -42,18 +42,13 @@ machine-$(CONFIG_PPC64) += 64
> >  machine-$(CONFIG_CPU_LITTLE_ENDIAN) += le
> >  UTS_MACHINE := $(subst $(space),,$(machine-y))
> >
> > -# XXX This needs to be before we override LD below
> > -ifdef CONFIG_PPC32
> > -KBUILD_LDFLAGS_MODULE += arch/powerpc/lib/crtsavres.o
> > -else
> > -ifeq ($(call ld-ifversion, -ge, 22500, y),y)
> > +ifeq ($(CONFIG_PPC64)$(CONFIG_LD_IS_BFD),yy)
> >  # Have the linker provide sfpr if possible.
> >  # There is a corresponding test in arch/powerpc/lib/Makefile
> >  KBUILD_LDFLAGS_MODULE += --save-restore-funcs
> >  else
> >  KBUILD_LDFLAGS_MODULE += arch/powerpc/lib/crtsavres.o
> >  endif
> > -endif
> >
> >  ifdef CONFIG_CPU_LITTLE_ENDIAN
> >  KBUILD_CFLAGS  += -mlittle-endian
> > @@ -389,8 +384,6 @@ vdso_prepare: prepare0
> >                 $(build)=arch/powerpc/kernel/vdso include/generated/vdso64-offsets.h)
> >  endif
> >
> > -archprepare: checkbin
> > -
> >  archheaders:
> >         $(Q)$(MAKE) $(build)=arch/powerpc/kernel/syscalls all
> >
> > @@ -405,16 +398,3 @@ else
> >         $(eval KBUILD_CFLAGS += -mstack-protector-guard-offset=$(shell awk '{if ($$2 == "TASK_CANARY") print $$3;}' include/generated/asm-offsets.h))
> >  endif
> >  endif
> > -
> > -PHONY += checkbin
> > -# Check toolchain versions:
> > -# - gcc-4.6 is the minimum kernel-wide version so nothing required.
> > -checkbin:
> > -       @if test "x${CONFIG_LD_IS_LLD}" != "xy" -a \
> > -               "x$(call ld-ifversion, -le, 22400, y)" = "xy" ; then \
> > -               echo -n '*** binutils 2.24 miscompiles weak symbols ' ; \
> > -               echo 'in some circumstances.' ; \
> > -               echo    '*** binutils 2.23 do not define the TOC symbol ' ; \
> > -               echo -n '*** Please use a different binutils version.' ; \
> > -               false ; \
> > -       fi
> > diff --git a/arch/powerpc/lib/Makefile b/arch/powerpc/lib/Makefile
> > index 4de71cbf6e8e..c53618c34b70 100644
> > --- a/arch/powerpc/lib/Makefile
> > +++ b/arch/powerpc/lib/Makefile
> > @@ -42,7 +42,7 @@ obj-$(CONFIG_FUNCTION_ERROR_INJECTION)        += error-inject.o
> >  # 64-bit linker creates .sfpr on demand for final link (vmlinux),
> >  # so it is only needed for modules, and only for older linkers which
> >  # do not support --save-restore-funcs
> > -ifeq ($(call ld-ifversion, -lt, 22500, y),y)
> > +ifndef CONFIG_LD_IS_BFD
> >  extra-$(CONFIG_PPC64)  += crtsavres.o
> >  endif
> >
> > diff --git a/scripts/Makefile.compiler b/scripts/Makefile.compiler
> > index 3d8adfd34af1..ad07a4efc253 100644
> > --- a/scripts/Makefile.compiler
> > +++ b/scripts/Makefile.compiler
> > @@ -72,7 +72,3 @@ clang-min-version = $(call test-ge, $(CONFIG_CLANG_VERSION), $1)
> >  # ld-option
> >  # Usage: KBUILD_LDFLAGS += $(call ld-option, -X, -Y)
> >  ld-option = $(call try-run, $(LD) $(KBUILD_LDFLAGS) $(1) -v,$(1),$(2),$(3))
> > -
> > -# ld-ifversion
> > -# Usage:  $(call ld-ifversion, -ge, 22252, y)
> > -ld-ifversion = $(shell [ $(CONFIG_LD_VERSION)0 $(1) $(2)0 ] && echo $(3) || echo $(4))
> > --
> > 2.34.1
> >


-- 
Best Regards
Masahiro Yamada