From: Russell King rmk+kernel@armlinux.org.uk
[ Upstream commit f3f2364ea14d1cf6bf966542f31eadcf178f1577 ]
phylink requires the MAC to report when its link status changes when operating in inband modes. Failure to report link status changes means that phylink has no idea when the link events happen, which results in either the network interface's carrier remaining up or remaining permanently down.
For example, with a fiber module, if the interface is brought up and link is initially established, taking the link down at the far end will cut the optical power. The SFP module's LOS asserts, we deactivate the link, and the network interface reports no carrier.
When the far end is brought back up, the SFP module's LOS deasserts, but the MAC may be slower to establish link. If this happens (which in my tests is a certainty) then phylink never hears that the MAC has established link with the far end, and the network interface is stuck reporting no carrier. This means the interface is non-functional.
Avoiding the link interrupt when we have phylink is basically not an option, so remove the !port->phylink from the test.
Fixes: 4bb043262878 ("net: mvpp2: phylink support") Tested-by: Sven Auhagen sven.auhagen@voleatech.de Tested-by: Antoine Tenart antoine.tenart@bootlin.com Signed-off-by: Russell King rmk+kernel@armlinux.org.uk Signed-off-by: Jakub Kicinski jakub.kicinski@netronome.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c +++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c @@ -3674,7 +3674,7 @@ static int mvpp2_open(struct net_device valid = true; }
- if (priv->hw_version == MVPP22 && port->link_irq && !port->phylink) { + if (priv->hw_version == MVPP22 && port->link_irq) { err = request_irq(port->link_irq, mvpp2_link_status_isr, 0, dev->name, port); if (err) {