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Date:   Tue, 18 Feb 2020 05:48:00 +0100
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     Daniel Jordan <daniel.m.jordan@oracle.com>
Cc:     Sasha Levin <sashal@kernel.org>,
        Steffen Klassert <steffen.klassert@secunet.com>,
        linux-kernel@vger.kernel.org,
        Herbert Xu <herbert@gondor.apana.org.au>,
        stable@vger.kernel.org
Subject: Re: [PATCH v2 4.14] padata: Remove broken queue flushing
Message-ID: <20200218044800.GA2048254@kroah.com>
References: <20200213151948.275124464@linuxfoundation.org>
 <20200214194651.442848-1-daniel.m.jordan@oracle.com>
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On Fri, Feb 14, 2020 at 02:46:51PM -0500, Daniel Jordan wrote:
> From: Herbert Xu <herbert@gondor.apana.org.au>
> 
> [ Upstream commit 07928d9bfc81640bab36f5190e8725894d93b659 ]
> 
> The function padata_flush_queues is fundamentally broken because
> it cannot force padata users to complete the request that is
> underway.  IOW padata has to passively wait for the completion
> of any outstanding work.
> 
> As it stands flushing is used in two places.  Its use in padata_stop
> is simply unnecessary because nothing depends on the queues to
> be flushed afterwards.
> 
> The other use in padata_replace is more substantial as we depend
> on it to free the old pd structure.  This patch instead uses the
> pd->refcnt to dynamically free the pd structure once all requests
> are complete.
> 
> Fixes: 2b73b07ab8a4 ("padata: Flush the padata queues actively")
> Cc: <stable@vger.kernel.org>
> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
> [dj: leave "pd->pinst = pinst" assignment in padata_alloc_pd()]
> Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>

Thanks, all 3 backports now queued up.

greg k-h