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Date:   Wed, 27 Nov 2019 18:38:40 -0500
From:   Daniel Jordan <daniel.m.jordan@oracle.com>
To:     Herbert Xu <herbert@gondor.apana.org.au>
Cc:     Daniel Jordan <daniel.m.jordan@oracle.com>,
        Eric Biggers <ebiggers@kernel.org>,
        Linux Crypto Mailing List <linux-crypto@vger.kernel.org>,
        Steffen Klassert <steffen.klassert@secunet.com>
Subject: Re: [v3 PATCH] crypto: pcrypt - Avoid deadlock by using per-instance
 padata queues
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On Tue, Nov 26, 2019 at 03:58:45PM +0800, Herbert Xu wrote:
> On Tue, Nov 26, 2019 at 12:32:38AM -0500, Daniel Jordan wrote:
> > 
> > I think it's possible for a task in padata_do_parallel() racing with another in
> > padata_replace() to use a pd after free.  The synchronize_rcu() comes after the
> > pd_old->refcnt's are dec'd.
> 
> Thanks.  I've fixed this as well as the CPU mask issue you identified
> earlier.

I spent some time reviewing and testing this today, and the changes to
padata.h/c look fine to me.

Daniel