From 1b614fb9a00e97b1eab54d4e442d405229c059dd Mon Sep 17 00:00:00 2001 From: Anton Vorontsov Date: Wed, 8 Jul 2009 20:09:44 -0700 Subject: netpoll: Fix carrier detection for drivers that are using phylib Using early netconsole and gianfar driver this error pops up: netconsole: timeout waiting for carrier It appears that net/core/netpoll.c:netpoll_setup() is using cond_resched() in a loop waiting for a carrier. The thing is that cond_resched() is a no-op when system_state != SYSTEM_RUNNING, and so drivers/net/phy/phy.c's state_queue is never scheduled, therefore link detection doesn't work. I belive that the main problem is in cond_resched()[1], but despite how the cond_resched() story ends, it might be a good idea to call msleep(1) instead of cond_resched(), as suggested by Andrew Morton. [1] http://lkml.org/lkml/2009/7/7/463 Signed-off-by: Anton Vorontsov Signed-off-by: David S. Miller --- net/core/netpoll.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/core/netpoll.c') diff --git a/net/core/netpoll.c b/net/core/netpoll.c index 9675f312830d..df30feb2fc72 100644 --- a/net/core/netpoll.c +++ b/net/core/netpoll.c @@ -740,7 +740,7 @@ int netpoll_setup(struct netpoll *np) np->name); break; } - cond_resched(); + msleep(1); } /* If carrier appears to come up instantly, we don't -- cgit v1.2.3 From 79b1bee888d43b14cf0c08fb8e5aa6cb161e48f8 Mon Sep 17 00:00:00 2001 From: Dongdong Deng Date: Fri, 21 Aug 2009 03:33:36 +0000 Subject: netpoll: warning for ndo_start_xmit returns with interrupts enabled WARN_ONCE for ndo_start_xmit() enable interrupts in netpoll_send_skb(), because the NETPOLL API requires that interrupts remain disabled in netpoll_send_skb(). Signed-off-by: Dongdong Deng Acked-by: Matt Mackall Signed-off-by: David S. Miller --- net/core/netpoll.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'net/core/netpoll.c') diff --git a/net/core/netpoll.c b/net/core/netpoll.c index df30feb2fc72..1b76eb11deb4 100644 --- a/net/core/netpoll.c +++ b/net/core/netpoll.c @@ -319,6 +319,11 @@ static void netpoll_send_skb(struct netpoll *np, struct sk_buff *skb) udelay(USEC_PER_POLL); } + + WARN_ONCE(!irqs_disabled(), + "netpoll_send_skb(): %s enabled interrupts in poll (%pF)\n", + dev->name, ops->ndo_start_xmit); + local_irq_restore(flags); } -- cgit v1.2.3