On 10/12/2017 12:49 PM, Herbert Xu wrote: > On Thu, Oct 12, 2017 at 09:39:34AM +0000, Horia Geantă wrote: >> >> Taking ascii art from crypto API docs: >> >> DATA -----------. >> v >> .init() -> .update() -> .final() ! .update() might not be called >> ^ | | at all in this scenario. >> '----' '---> HASH >> >> My question was referring to the case where multiple update() operations >> are issued in parallel for the same request object. >> For e.g. let's say a crypto API client wants to hash a 4GB file, and >> does this by issuing update() repeatedly and performing >> wait_for_completion() at the very end. > > That is most certainly not legal. Is dm-crypt doing that? > dm-crypt is issuing requests (aead / skcipher) in parallel, however a new request object is allocated each time, which seems legit. My confusion was due to mixing parallelism at different levels: -at request object level - issuing multiple requests for the same request object (ahash update() case) -at tfm object level - issuing multiple requests for different request objects (dm-crypt case) As you pointed out, the first is not legal, while the latter is perfectly fine. Thanks, Horia
