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Date:   Sat, 23 Jan 2021 21:09:28 -0800
From:   Jakub Kicinski <kuba@kernel.org>
To:     Lijun Pan <ljp@linux.ibm.com>
Cc:     netdev@vger.kernel.org
Subject: Re: [PATCH net 2/3] ibmvnic: remove unnecessary rmb() inside
 ibmvnic_poll
Message-ID: <20210123210928.30d79969@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>
In-Reply-To: <20210121061710.53217-3-ljp@linux.ibm.com>
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        <20210121061710.53217-3-ljp@linux.ibm.com>
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On Thu, 21 Jan 2021 00:17:09 -0600 Lijun Pan wrote:
> rmb() was introduced to load rx_scrq->msgs after calling
> pending_scrq(). Now since pending_scrq() itself already
> has dma_rmb() at the end of the function, rmb() is
> duplicated and can be removed.
> 
> Fixes: ec20f36bb41a ("ibmvnic: Correctly re-enable interrupts in NAPI polling routine")
> Signed-off-by: Lijun Pan <ljp@linux.ibm.com>

rmb() is a stronger barrier than dma_rmb()

also again, I don't see how this fixes any bugs