Re: [PATCH v4 0/7] x86/boot: Remove runtime relocations from compressed kernel

From: Sedat Dilek
Date: Tue Jul 14 2020 - 14:33:34 EST


On Tue, Jul 14, 2020 at 8:30 PM Sedat Dilek <sedat.dilek@xxxxxxxxx> wrote:
>
> > I did a full new build...
> >
> > ...and it fails with ld.lld-11 as linker:
> >
> > ld.lld-11 -m elf_x86_64 -pie --no-dynamic-linker -r -o
> > arch/x86/boot/compressed/.tmp_misc.o arch/x86/boot/compressed/misc.o
> > -T arch/x86/boot/compressed/.tmp_misc.ver; mv -f
> > arch/x86/boot/compressed/.tmp_misc.o arch/x86/boot/compressed/misc.o;
> > rm -f arch/x86/boot/compressed/.tmp_misc.ver; fi
> > *** ld.lld-11: error: -r and -pie may not be used together ***
> > make[5]: *** [scripts/Makefile.build:281:
> > arch/x86/boot/compressed/misc.o] Error 1
> >
> > It's annoying to fail on the last minutes of a build.
> > Sorry for being very honest.
> >
>
> I applied this diff...
>
> $ git diff arch/x86/boot/compressed/Makefile
> diff --git a/arch/x86/boot/compressed/Makefile
> b/arch/x86/boot/compressed/Makefile
> index 789d5d14d8b0..9ba52a656838 100644
> --- a/arch/x86/boot/compressed/Makefile
> +++ b/arch/x86/boot/compressed/Makefile
> @@ -51,7 +51,10 @@ UBSAN_SANITIZE :=n
> KBUILD_LDFLAGS := -m elf_$(UTS_MACHINE)
> # Compressed kernel should be built as PIE since it may be loaded at any
> # address by the bootloader.
> +# LLD linker does not allow -r and -pie options to be used together.
> +ifndef CONFIG_LD_IS_LLD
> KBUILD_LDFLAGS += -pie $(call ld-option, --no-dynamic-linker)
> +endif
> LDFLAGS_vmlinux := -T
>
> hostprogs := mkpiggy
>
> ...and was able to build, assemble, link arch/x86/boot/compressed/*.
>

I checked my last succesfull build without your patchset:

$ grep no-dynamic-linker build-log_5.8.0-rc5-1-amd64-llvm11-ias.txt
[ EMPTY ]

- Sedat -