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Date:   Mon, 27 Jan 2020 17:04:13 +0100
From:   Andrew Lunn <andrew@lunn.ch>
To:     Vladimir Oltean <olteanv@gmail.com>
Cc:     madalin.bucur@oss.nxp.com, "David S. Miller" <davem@davemloft.net>,
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        Heiner Kallweit <hkallweit1@gmail.com>,
        netdev <netdev@vger.kernel.org>, ykaukab@suse.de
Subject: Re: [PATCH v2 2/2] dpaa_eth: support all modes with rate adapting
 PHYs
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> Is this sufficient?
> I suppose this works because you have flow control enabled by default?
> What would happen if the user would disable flow control with ethtool?

It will still work. Network protocols expect packets to be dropped,
there are bottlenecks on the network, and those bottlenecks change
dynamically. TCP will still be able to determine how much traffic it
can send without too much packet loss, independent of if the
bottleneck is here between the MAC and the PHY, or later when it hits
an RFC 1149 link.

    Andrew