Re: [RFC][PATCH 00/18] crypto: Add generic Kerberos library

[Chuck Lever]

> On Nov 12, 2020, at 4:07 PM, Bruce Fields <bfields@xxxxxxxxxxxx> wrote:
> 
> On Thu, Nov 12, 2020 at 04:54:06PM +0000, David Howells wrote:
>> Chuck Lever <chuck.lever@xxxxxxxxxx> wrote:
>> 
>>> Really? My understanding of the Linux kernel SUNRPC implementation is
>>> that it uses asynchronous, even for small data items. Maybe I'm using
>>> the terminology incorrectly.
>> 
>> Seems to be synchronous, at least in its use of skcipher:
> 
> Yes, it's all synchronous.  The only cases where we defer and revisit a
> request is when we need to do upcalls to userspace.
> 
> (And those upcalls mostly come after we're done with unwrapping and
> verifying a request, so now I'm sort of curious exactly what Chuck was
> seeing.)

I vaguely recall that setting CRYPTO_TFM_REQ_MAY_SLEEP allows the
crypto API to sleep and defer completion.


--
Chuck Lever