RE: [PATCH net-next 5/7] qlcnic: fix default operating state of interface

-----Original Message-----
From: Stephen Hemminger [mailto:shemminger@vyatta.com]

David Miller [off-list ref] wrote:

quoted

From: Anirban Chakraborty <redacted>
Date: Thu, 16 Jun 2011 13:37:36 -0700

quoted

From: Amit Kumar Salecha <redacted>

Currently interface shows status as RUNNING, even if there is no

link.

quoted

quoted

To fix this, netif_carrier_off should be called after

register_netdev().

quoted

quoted

netif_carrier_off calls linkwatch_fire_event(dev); only if netdev

is registered,

quoted

quoted

otherwise it skips. linkwatch_fire_event set default state of nic

interface.

quoted

quoted

Signed-off-by: Amit Kumar Salecha <redacted>
Signed-off-by: Anirban Chakraborty <redacted>

You cannot do this.

The exact second that register_netdev() is called, the device can
be brought up asynchronously and the link brought into the up state.

Your netif_carrier_off() call will race with this.

This is why no other (properly functioning) driver does what you're
trying to do here.

The proper place to do this is in the open() routine.
When device is not open, the carrier state is undefined; and devices
that are trying to save power turn off PHY when device is not in use.

Therefore the open() routine should ensure that the carrier is in
the proper state when returning. Just doing something like:

static int qlcnic_open() {
...
	netif_carrier_off()

        err = __qlcnic_up();
	...
}

static int __qlcnic_up() {
	...
	(lots of tests)
	...

        netif_carrier_on();
	adapter->reset_context = 0;
	set_bit(__QLCNIC_DEV_UP, &adapter->state);
	return 0;
}

netif_carrier_off() is ok, should be call from qlcnic_open().
netif_carrier_on() will be call during asynchronous notification from fw.

-Thanks.