Commit 97b01291 authored by Dave Ertman's avatar Dave Ertman Committed by Tony Nguyen
Browse files

ice: Fix error with handling of bonding MTU 



When a bonded interface is destroyed, .ndo_change_mtu can be called
during the tear-down process while the RTNL lock is held.  This is a
problem since the auxiliary driver linked to the LAN driver needs to be
notified of the MTU change, and this requires grabbing a device_lock on
the auxiliary_device's dev.  Currently this is being attempted in the
same execution context as the call to .ndo_change_mtu which is causing a
dead-lock.

Move the notification of the changed MTU to a separate execution context
(watchdog service task) and eliminate the "before" notification.

Fixes: 348048e7 ("ice: Implement iidc operations")
Signed-off-by: default avatarDave Ertman <david.m.ertman@intel.com>
Tested-by: default avatarJonathan Toppins <jtoppins@redhat.com>
Tested-by: Gurucharan G <gurucharanx.g@intel.com> (A Contingent worker at Intel)
Signed-off-by: default avatarTony Nguyen <anthony.l.nguyen@intel.com>
parent 79498d5a

drivers/net/ethernet/intel/ice/ice.h

+1 −0
Original line number Diff line number Diff line
@@ -483,6 +483,7 @@ enum ice_pf_flags { 
	ICE_FLAG_MDD_AUTO_RESET_VF,

	ICE_FLAG_LINK_LENIENT_MODE_ENA,

	ICE_FLAG_PLUG_AUX_DEV,

	ICE_FLAG_MTU_CHANGED,

	ICE_PF_FLAGS_NBITS		/* must be last */

};

drivers/net/ethernet/intel/ice/ice_main.c

+14 −15
Original line number Diff line number Diff line
@@ -2258,6 +2258,17 @@ static void ice_service_task(struct work_struct *work) 
	if (test_and_clear_bit(ICE_FLAG_PLUG_AUX_DEV, pf->flags))

		ice_plug_aux_dev(pf);



	if (test_and_clear_bit(ICE_FLAG_MTU_CHANGED, pf->flags)) {

		struct iidc_event *event;



		event = kzalloc(sizeof(*event), GFP_KERNEL);

		if (event) {

			set_bit(IIDC_EVENT_AFTER_MTU_CHANGE, event->type);

			ice_send_event_to_aux(pf, event);

			kfree(event);

		}

	}



	ice_clean_adminq_subtask(pf);

	ice_check_media_subtask(pf);

	ice_check_for_hang_subtask(pf);
@@ -6822,7 +6833,6 @@ static int ice_change_mtu(struct net_device *netdev, int new_mtu) 
	struct ice_netdev_priv *np = netdev_priv(netdev);

	struct ice_vsi *vsi = np->vsi;

	struct ice_pf *pf = vsi->back;

	struct iidc_event *event;

	u8 count = 0;

	int err = 0;
@@ -6857,14 +6867,6 @@ static int ice_change_mtu(struct net_device *netdev, int new_mtu) 
		return -EBUSY;

	}



	event = kzalloc(sizeof(*event), GFP_KERNEL);

	if (!event)

		return -ENOMEM;



	set_bit(IIDC_EVENT_BEFORE_MTU_CHANGE, event->type);

	ice_send_event_to_aux(pf, event);

	clear_bit(IIDC_EVENT_BEFORE_MTU_CHANGE, event->type);



	netdev->mtu = (unsigned int)new_mtu;



	/* if VSI is up, bring it down and then back up */
@@ -6872,21 +6874,18 @@ static int ice_change_mtu(struct net_device *netdev, int new_mtu) 
		err = ice_down(vsi);

		if (err) {

			netdev_err(netdev, "change MTU if_down err %d\n", err);

			goto event_after;

			return err;

		}



		err = ice_up(vsi);

		if (err) {

			netdev_err(netdev, "change MTU if_up err %d\n", err);

			goto event_after;

			return err;

		}

	}



	netdev_dbg(netdev, "changed MTU to %d\n", new_mtu);

event_after:

	set_bit(IIDC_EVENT_AFTER_MTU_CHANGE, event->type);

	ice_send_event_to_aux(pf, event);

	kfree(event);

	set_bit(ICE_FLAG_MTU_CHANGED, pf->flags);



	return err;

}