[PATCH] netdev: carrier detect ok, don't turn off negotiation

[PATCH] netdev: carrier detect ok, don't turn off negotiation

[Denis Du]

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.

Signed-off-by: Denis Du <dudenis2000@yahoo.ca>
---
 drivers/net/wan/hdlc_ppp.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wan/hdlc_ppp.c b/drivers/net/wan/hdlc_ppp.c
index afeca6b..ab8b3cb 100644
--- a/drivers/net/wan/hdlc_ppp.c
+++ b/drivers/net/wan/hdlc_ppp.c
@@ -574,7 +574,10 @@ static void ppp_timer(struct timer_list *t)
 			ppp_cp_event(proto->dev, proto->pid, TO_GOOD, 0, 0,
 				     0, NULL);
 			proto->restart_counter--;
-		} else
+		} else if (netif_carrier_ok(proto->dev))
+			ppp_cp_event(proto->dev, proto->pid, TO_GOOD, 0, 0,
+				     0, NULL);
+		else
 			ppp_cp_event(proto->dev, proto->pid, TO_BAD, 0, 0,
 				     0, NULL);
 		break;
-- 
2.1.4

Re: [PATCH] netdev: carrier detect ok, don't turn off negotiation

[David Miller]

From: Denis Du <dudenis2000@yahoo.ca>
Date: Sat, 24 Feb 2018 16:51:42 -0500

> 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.
> 
> Signed-off-by: Denis Du <dudenis2000@yahoo.ca>

Applied and queued up for -stable, thanks.