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Date:   Mon, 22 Jan 2018 22:17:06 +0000 (UTC)
From:   Denis Du <dudenis2000@yahoo.ca>
To:     David Miller <davem@davemloft.net>
Cc:     khc@pm.waw.pl, netdev@vger.kernel.org, linux-kernel@vger.kernel.org
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Subject: Re: [PATCH] Carrier detect ok, don't turn off negotiation
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The timer is supposed to be triggered by carrier detect interrupt. After re=
move the line noise, the carrier detect interrupt is never triggered again,=
 because the carrier is always ok and it only trigger the timer once, Since=
 the protocol was terminated and no new interrupts happen, the link will ne=
ver be back. So the case here is that the line noise is good and just good =
to make the carrier detect still good=C2=A0 but the protocol fail, the time=
r will be never triggered again.

Of course, if you increase the noise and make even the carrier detect fail,=
 then remove the noise, the link will be up, Because the carrier down and u=
p again and then trigger the timer to restart.

Denis Du


On Monday, January 22, 2018, 3:25:16 PM EST, David Miller <davem@davemloft.=
net> wrote:=20


From: Denis Du <dudenis2000@yahoo.ca>
Date: Tue, 16 Jan 2018 16:58:25 +0000 (UTC)

> From b5902a4dfc709b62b704997ab64f31c9ef69a6db Mon Sep 17 00:00:00 2001
> From: Denis Du <dudenis2000@yahoo.ca>
> Date: Mon, 15 Jan 2018 17:26:06 -0500
> Subject: [PATCH] netdev: carrier detect ok, don't turn off negotiation
>=20
> Sometimes when physical lines have a just good noise to make the protocol
> handshaking fail, but the carrier detect still good. Then after remove of
> the noise, nobody will trigger this protocol to be start again to cause
> the link to never come back. The fix is when the carrier is still on, not
> terminate the protocol handshaking.
>=20
> Signed-off-by: Denis Du <dudenis2000@yahoo.ca>

The timer is supposed to restart the protocol again, that's how this
whole thing is designed to work.

I think you are making changes to the symptom rather than the true
cause of the problems you are seeing.

Sorry, I will not apply this until the exact issue is better
understood.

Thank you.