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Date:   Thu, 22 Jul 2021 17:01:30 +0300
From:   Leon Romanovsky <leon@kernel.org>
To:     Jason Gunthorpe <jgg@nvidia.com>
Cc:     Dakshaja Uppalapati <dakshaja@chelsio.com>, dledford@redhat.com,
        linux-rdma@vger.kernel.org, bharat@chelsio.com
Subject: Re: [PATCH for-rc] iw_cxgb4: Fix refcount underflow while destroying
 cqs.
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 <20210722120607.GE1117491@nvidia.com>
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On Thu, Jul 22, 2021 at 10:02:31AM -0300, Jason Gunthorpe wrote:
> On Thu, Jul 22, 2021 at 03:57:39PM +0300, Leon Romanovsky wrote:
> 
> > We are talking about two different issues that this refcount_read patch pointed.
> > You are focused on wrong usage of completion, I saw useless compare of
> > refcount_t with 0 that can't be.
> 
> It can be zero. Anything that does refcount_dec_and_test() can make
> the refcount be zero.

It can be, but it is not the case at least for iwpm.

Thanks