Hi Elliott, Robert
Thanks for your review!
2022. 8. 27. 오전 12:12에 Elliott, Robert (Servers) 이(가) 쓴 글:
>
>
>> -----Original Message-----
>> From: Taehee Yoo <ap420073@xxxxxxxxx>
>> Sent: Friday, August 26, 2022 12:32 AM
>> Subject: [PATCH v2 2/3] crypto: aria-avx: add AES-NI/AVX/x86_64
assembler
>> implementation of aria cipher
>>
>> v2:
>> - Do not call non-FPU functions(aria_{encrypt | decrypt}() in the
>> FPU context.
>> - Do not acquire FPU context for too long.
>
> ...
>> +static int ecb_do_encrypt(struct skcipher_request *req, const u32
*rkey)
>> +{
> ...
>> + while ((nbytes = walk.nbytes) > 0) {
>> + const u8 *src = walk.src.virt.addr;
>> + u8 *dst = walk.dst.virt.addr;
>> +
>> + kernel_fpu_begin();
>> + while (nbytes >= ARIA_AVX_BLOCK_SIZE) {
>> + aria_aesni_avx_crypt_16way(rkey, dst, src, ctx->rounds);
>> + dst += ARIA_AVX_BLOCK_SIZE;
>> + src += ARIA_AVX_BLOCK_SIZE;
>> + nbytes -= ARIA_AVX_BLOCK_SIZE;
>> + }
>> + kernel_fpu_end();
>
> Per Herbert's reply on the sha512-avx RCU stall issue, another nesting
> level might be necessary limiting the amount of data processed between
> each kernel_fpu_begin() to kernel_fpu_end() pair to 4 KiB.
>
> If you modify this driver to use the ECB_WALK_START, ECB_BLOCK, and
> ECB_WALK_END macros from ecb_cbc_helpers.h and incorporate that fix,
> then your fix would be easy to replicate into the other users (camellia,
> cast5, cast6, serpent, and twofish).
>
Now I understand why you suggested using ECB macro instead of open code.
I think your idea is nice for many users such as camellia, cast5, etc.
I will use ECB macro in the v3 patch.
Then, I will send a fixing the RCU stall issue patch separately instead
of containing it.
Thanks a lot!
Taehee Yoo
