Re: [PATCH] padata: Remove broken queue flushing

[Herbert Xu]

On Tue, Nov 19, 2019 at 05:44:32PM -0500, Daniel Jordan wrote:
> 
> I assume you mean the third patch you recently posted, "crypto: pcrypt - Avoid
> deadlock by using per-instance padata queues".  That's true, the problem is
> fixed there, and the bug being present in bisection doesn't seem like enough
> justification to implement something short-lived just to prevent it.

Right.  But as pcrypt is the only user this should still work.
 
> Makes sense to me, though I don't see how it's enforced now in pcrypt.  I'm not
> an async crypto person, but wouldn't unloading the pcrypt module when there are
> still outstanding async jobs break this rule?

It's enforced through module reference counting.  While there are
any outstanding requests, there must be allocated crypto tfms.  Each
crypto tfm maintains a module reference count on pcrypt which
prevents it from being unloaded.

> Actually, I'm working on an RFC right now to add more users for padata.  It
> should be posted in the coming week or two, and I hope it can be part of that
> discussion.

OK.

Cheers,
-- 
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
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