Re: [PATCH] crypto: arm/sha256-neon - Fix clang function cast warnings

From: Nick Desaulniers
Date: Wed Apr 19 2023 - 17:54:04 EST


On Wed, Apr 19, 2023 at 2:32 AM Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> wrote:
>
> Instead of casting the function which upsets clang for some reason,
> change the assembly function siganture instead.

Thanks for the patch, same comments as the sha1 patch:
https://lore.kernel.org/oe-kbuild-all/CAKwvOdm2VyCzfmG6707osmtyniV-oL-ism08kER49D7p_7x+Rg@xxxxxxxxxxxxxx/
though sha256_block_data_order_neon is defined in
arch/arm/crypto/sha256-armv4.pl and does not have any comments about
the function signature.
Also, I see a few more casts to sha256_block_fn:

arch/arm/crypto/sha256_glue.c
37: (sha256_block_fn *)sha256_block_data_order);
44: (sha256_block_fn *)sha256_block_data_order);
52: (sha256_block_fn *)sha256_block_data_order);

arch/arm/crypto/sha2-ce-glue.c
41: (sha256_block_fn *)sha2_ce_transform);
56: (sha256_block_fn *)sha2_ce_transform);
57: sha256_base_do_finalize(desc, (sha256_block_fn *)sha2_ce_transform);

Can those be cleaned up, too? (Either in this patch or a follow up?)

>
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> Link: https://lore.kernel.org/oe-kbuild-all/202304081828.zjGcFUyE-lkp@xxxxxxxxx/
> Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
>
> diff --git a/arch/arm/crypto/sha256_neon_glue.c b/arch/arm/crypto/sha256_neon_glue.c
> index 701706262ef3..ccdcfff71910 100644
> --- a/arch/arm/crypto/sha256_neon_glue.c
> +++ b/arch/arm/crypto/sha256_neon_glue.c
> @@ -21,8 +21,8 @@
>
> #include "sha256_glue.h"
>
> -asmlinkage void sha256_block_data_order_neon(u32 *digest, const void *data,
> - unsigned int num_blks);
> +asmlinkage void sha256_block_data_order_neon(struct sha256_state *digest,
> + const u8 *data, int num_blks);
>
> static int crypto_sha256_neon_update(struct shash_desc *desc, const u8 *data,
> unsigned int len)
> @@ -34,8 +34,7 @@ static int crypto_sha256_neon_update(struct shash_desc *desc, const u8 *data,
> return crypto_sha256_arm_update(desc, data, len);
>
> kernel_neon_begin();
> - sha256_base_do_update(desc, data, len,
> - (sha256_block_fn *)sha256_block_data_order_neon);
> + sha256_base_do_update(desc, data, len, sha256_block_data_order_neon);
> kernel_neon_end();
>
> return 0;
> @@ -50,9 +49,8 @@ static int crypto_sha256_neon_finup(struct shash_desc *desc, const u8 *data,
> kernel_neon_begin();
> if (len)
> sha256_base_do_update(desc, data, len,
> - (sha256_block_fn *)sha256_block_data_order_neon);
> - sha256_base_do_finalize(desc,
> - (sha256_block_fn *)sha256_block_data_order_neon);
> + sha256_block_data_order_neon);
> + sha256_base_do_finalize(desc, sha256_block_data_order_neon);
> kernel_neon_end();
>
> return sha256_base_finish(desc, out);
> --
> Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
> Home Page: http://gondor.apana.org.au/~herbert/
> PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
>


--
Thanks,
~Nick Desaulniers