On 07/17/2017 10:41 PM, Herbert Xu wrote:
> On Tue, Jun 27, 2017 at 05:26:13PM -0700, Megha Dey wrote:
>>
>> +static void completion_callback(struct mcryptd_skcipher_request_ctx *rctx,
>> + struct mcryptd_alg_cstate *cstate,
>> + int err)
>> +{
>> + struct skcipher_request *req = cast_mcryptd_ctx_to_req(rctx);
>> +
>> + /* remove from work list and invoke completion callback */
>> + spin_lock(&cstate->work_lock);
>> + list_del(&rctx->waiter);
>> + spin_unlock(&cstate->work_lock);
>> +
>> + if (irqs_disabled())
>> + rctx->complete(&req->base, err);
>> + else {
>> + local_bh_disable();
>> + rctx->complete(&req->base, err);
>> + local_bh_enable();
>> + }
>> +}
>
> The fact that you need to do this check means that this design is
> wrong. You should always know what context you are in.
>
I think you are right. The irqs_disabled check is not necessary
as we only call this function in the context of the mcryptd thread.
When I wrote the original mb algorithms I was probably unsure
and put this check in as a precaution in other mb algorithms and
Megha did the same.
>> +/*
>> + * CRYPTO_ALG_ASYNC flag is passed to indicate we have an ablk
>> + * scatter-gather walk.
>> + */
>> +static struct skcipher_alg aes_cbc_mb_alg = {
>> + .base = {
>> + .cra_name = "cbc(aes)",
>> + .cra_driver_name = "cbc-aes-aesni-mb",
>> + .cra_priority = 500,
>> + .cra_flags = CRYPTO_ALG_INTERNAL,
>> + .cra_blocksize = AES_BLOCK_SIZE,
>> + .cra_ctxsize = CRYPTO_AES_CTX_SIZE,
>> + .cra_module = THIS_MODULE,
>> + },
>> + .min_keysize = AES_MIN_KEY_SIZE,
>> + .max_keysize = AES_MAX_KEY_SIZE,
>> + .ivsize = AES_BLOCK_SIZE,
>> + .setkey = aes_set_key,
>> + .encrypt = mb_aes_cbc_encrypt,
>> + .decrypt = mb_aes_cbc_decrypt
>> +};
>
> So this claims to be a sync algorithm. Is this really the case?
>
> Cheers,
>
