From 124eee3f6955f7aa19b9e6ff5c9b6d37cb3d1e2c Mon Sep 17 00:00:00 2001 From: Heiner Kallweit Date: Tue, 18 Sep 2018 21:55:36 +0200 Subject: [PATCH 1/2] net: linkwatch: add check for netdevice being present to linkwatch_do_dev When bringing down the netdevice (incl. detaching it) and calling netif_carrier_off directly or indirectly the latter triggers an asynchronous linkwatch event. This linkwatch event eventually may fail to access chip registers in the ndo_get_stats/ndo_get_stats64 callback because the device isn't accessible any longer, see call trace in [0]. To prevent this scenario don't check for IFF_UP only, but also make sure that the netdevice is present. [0] https://lists.openwall.net/netdev/2018/03/15/62 Signed-off-by: Heiner Kallweit Tested-by: Geert Uytterhoeven Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller --- net/core/link_watch.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/core/link_watch.c b/net/core/link_watch.c index e38e641e98d5..7f51efb2b3ab 100644 --- a/net/core/link_watch.c +++ b/net/core/link_watch.c @@ -155,7 +155,7 @@ static void linkwatch_do_dev(struct net_device *dev) clear_bit(__LINK_STATE_LINKWATCH_PENDING, &dev->state); rfc2863_policy(dev); - if (dev->flags & IFF_UP) { + if (dev->flags & IFF_UP && netif_device_present(dev)) { if (netif_carrier_ok(dev)) dev_activate(dev); else From e8cfd9d6c7727a067b38dbe7655ca02377fdb301 Mon Sep 17 00:00:00 2001 From: Heiner Kallweit Date: Tue, 18 Sep 2018 21:56:32 +0200 Subject: [PATCH 2/2] net: phy: call state machine synchronously in phy_stop phy_stop() may be called e.g. when suspending, therefore all needed actions should be performed synchronously. Therefore add a synchronous call to the state machine. Signed-off-by: Heiner Kallweit Tested-by: Geert Uytterhoeven Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller --- drivers/net/phy/phy.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c index 1ee25877c4d1..a5e0f0721035 100644 --- a/drivers/net/phy/phy.c +++ b/drivers/net/phy/phy.c @@ -861,6 +861,8 @@ void phy_stop(struct phy_device *phydev) out_unlock: mutex_unlock(&phydev->lock); + phy_state_machine(&phydev->state_queue.work); + /* Cannot call flush_scheduled_work() here as desired because * of rtnl_lock(), but PHY_HALTED shall guarantee phy_change() * will not reenable interrupts.