Re: [PATCH v6 2/2] s390/crypto: New s390 specific protected key hash phmac

[Herbert Xu <herbert@gondor.apana.org.au>]

On Fri, Nov 29, 2024 at 12:10:58PM +0100, Harald Freudenberger wrote:
>
> +static inline int phmac_keyblob2pkey(const u8 *key, unsigned int keylen,
> +				     struct phmac_protkey *pk)
> +{
> +	int i, rc = -EIO;
> +
> +	/* try three times in case of busy card */
> +	for (i = 0; rc && i < 3; i++) {
> +		if (rc == -EBUSY && msleep_interruptible(1000))
> +			return -EINTR;

You can't sleep in an ahash algorithm either.  What you can do
however is schedule a delayed work and pick up where you left
off.  That's how asynchronous completion works.

But my question still stands, under what circumstances can
this fail? I don't think storage folks will be too happy with
a crypto algorithm that can produce random failures.

Cheers,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt