| Message ID | 20170518090953.32628-1-ard.biesheuvel@linaro.org |
|---|---|
| Headers | show |
| Series | efi: arm64: use -fpie for building the stub | expand |
On 18 May 2017 at 10:09, Ard Biesheuvel <ard.biesheuvel@linaro.org> wrote: > Clang requires the stub to be built with -fpie, or it may emit absolute > symbol references that trigger the absolute relocation detection code and > cause the build to fail. > > The remedy is to set -fpie (#3), but due to stupid ELF symbol preemption > rules that only apply to shared libraries, this will result in more rather > than fewer absolute references (i.e., GOT entries), which we have to massage > away using visibility overrides first. (#1, #2) > > Ard Biesheuvel (3): > efi/libstub: arm64: use hidden attribute for struct screen_info > reference > efi/libstub: arm64: force 'hidden' visibility for section markers > efi/libstub: arm64: set -fpie when building the EFI stub > > arch/arm64/include/asm/efi.h | 3 +++ > drivers/firmware/efi/libstub/Makefile | 2 +- > drivers/firmware/efi/libstub/arm64-stub.c | 10 +++++++++- > 3 files changed, 13 insertions(+), 2 deletions(-) > I have queued these in efi/next, with Matthias's Tested-by -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Clang requires the stub to be built with -fpie, or it may emit absolute symbol references that trigger the absolute relocation detection code and cause the build to fail. The remedy is to set -fpie (#3), but due to stupid ELF symbol preemption rules that only apply to shared libraries, this will result in more rather than fewer absolute references (i.e., GOT entries), which we have to massage away using visibility overrides first. (#1, #2) Ard Biesheuvel (3): efi/libstub: arm64: use hidden attribute for struct screen_info reference efi/libstub: arm64: force 'hidden' visibility for section markers efi/libstub: arm64: set -fpie when building the EFI stub arch/arm64/include/asm/efi.h | 3 +++ drivers/firmware/efi/libstub/Makefile | 2 +- drivers/firmware/efi/libstub/arm64-stub.c | 10 +++++++++- 3 files changed, 13 insertions(+), 2 deletions(-) -- 2.9.3 -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html