Re: [PATCH v2 16/18] arm64: crypto: disable LTO for aes-ce-cipher.c

Mark Rutland
2017-11-20T15:20:20Z

On Wed, Nov 15, 2017 at 01:34:26PM -0800, Sami Tolvanen wrote:
> CONFIG_LTO_CLANG requires the use of clang's integrated assembler, which
> doesn't understand the inline assembly in aes-ce-cipher.c. Disable LTO for
> the file to work around the issue.

Could you elaborate on what the integrated asembler doesn't like?

It's not entirely clear at a glance, as the asm in that file doesn't
seem to do anything that obscure.

Is it a bug?

Thanks,
Mark.

> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
> ---
> arch/arm64/crypto/Makefile | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/arm64/crypto/Makefile b/arch/arm64/crypto/Makefile
> index b5edc5918c28..af08508521a3 100644
> --- a/arch/arm64/crypto/Makefile
> +++ b/arch/arm64/crypto/Makefile
> @@ -24,7 +24,7 @@ obj-$(CONFIG_CRYPTO_CRC32_ARM64_CE) += crc32-ce.o
> crc32-ce-y:= crc32-ce-core.o crc32-ce-glue.o
>
> obj-$(CONFIG_CRYPTO_AES_ARM64_CE) += aes-ce-cipher.o
> -CFLAGS_aes-ce-cipher.o += -march=armv8-a+crypto
> +CFLAGS_aes-ce-cipher.o += -march=armv8-a+crypto $(DISABLE_LTO_CLANG)
>
> obj-$(CONFIG_CRYPTO_AES_ARM64_CE_CCM) += aes-ce-ccm.o
> aes-ce-ccm-y := aes-ce-ccm-glue.o aes-ce-ccm-core.o
> --
> 2.15.0.448.gf294e3d99a-goog
>