RE: [PATCH 1/1] atl1c: fix issue of transmit queue 0 timed out

Yes, another fix to remove netif_stop_queue when cable link is down.

-Xiong

-----Original Message-----
From: Ben Hutchings [mailto:bhutchings@solarflare.com]
Sent: Wednesday, June 27, 2012 4:24
To: Ren, Cloud
Cc: davem@davemloft.net; netdev@vger.kernel.org; linux-
kernel@vger.kernel.org; qca-linux-team; nic-devel; Huang, Xiong
Subject: Re: [PATCH 1/1] atl1c: fix issue of transmit queue 0 timed out

On Tue, 2012-06-26 at 12:33 -0300, Ren, Cloud wrote:

quoted

From: xiong <redacted>

some people report atl1c could cause system hang with following kernel
trace info:
---------------------------------------
WARNING: at.../net/sched/sch_generic.c:258
dev_watchdog+0x1db/0x1d0()
...
NETDEV WATCHDOG: eth0 (atl1c): transmit queue 0 timed out ...
---------------------------------------
This is caused by netif_stop_queue calling when cable Link is down but
netif_wake_queue isn't called when cable Link is resume.

Signed-off-by: xiong <redacted>
Signed-off-by: Cloud Ren <redacted>
---
 drivers/net/ethernet/atheros/atl1c/atl1c_main.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/drivers/net/ethernet/atheros/atl1c/atl1c_main.c

b/drivers/net/ethernet/atheros/atl1c/atl1c_main.c
index 85717cb..c2736c4 100644

--- a/drivers/net/ethernet/atheros/atl1c/atl1c_main.c
+++ b/drivers/net/ethernet/atheros/atl1c/atl1c_main.c

@@ -351,6 +351,8 @@ static void atl1c_common_task(struct work_struct

*work)

quoted

 		atl1c_irq_disable(adapter);
 		atl1c_check_link_status(adapter);
 		atl1c_irq_enable(adapter);
+		if (netif_queue_stopped(netdev) && netif_carrier_ok(netdev))
+			netif_wake_queue(netdev);
 	}
 }

Why explicitly stop/start the queue when the link changes?  That's what
link_watch is for.

Ben.

--
Ben Hutchings, Staff Engineer, Solarflare Not speaking for my employer; that's
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