jme: Protect vlgrp structure by pause RX actions.

Temporary stop the RX IRQ, and disable (sync) tasklet or napi.
And restore it after finished the vlgrp pointer assignment.
Signed-off-by: NGuo-Fu Tseng <cooldavid@cooldavid.org>
Cc: stable@kernel.org
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/jme.c

@@ -2083,12 +2083,45 @@ jme_tx_timeout(struct net_device *netdev)
 	jme_reset_link(jme);
 }
 
+static inline void jme_pause_rx(struct jme_adapter *jme)
+{
+	atomic_dec(&jme->link_changing);
+
+	jme_set_rx_pcc(jme, PCC_OFF);
+	if (test_bit(JME_FLAG_POLL, &jme->flags)) {
+		JME_NAPI_DISABLE(jme);
+	} else {
+		tasklet_disable(&jme->rxclean_task);
+		tasklet_disable(&jme->rxempty_task);
+	}
+}
+
+static inline void jme_resume_rx(struct jme_adapter *jme)
+{
+	struct dynpcc_info *dpi = &(jme->dpi);
+
+	if (test_bit(JME_FLAG_POLL, &jme->flags)) {
+		JME_NAPI_ENABLE(jme);
+	} else {
+		tasklet_hi_enable(&jme->rxclean_task);
+		tasklet_hi_enable(&jme->rxempty_task);
+	}
+	dpi->cur		= PCC_P1;
+	dpi->attempt		= PCC_P1;
+	dpi->cnt		= 0;
+	jme_set_rx_pcc(jme, PCC_P1);
+
+	atomic_inc(&jme->link_changing);
+}
+
 static void
 jme_vlan_rx_register(struct net_device *netdev, struct vlan_group *grp)
 {
 	struct jme_adapter *jme = netdev_priv(netdev);
 
+	jme_pause_rx(jme);
 	jme->vlgrp = grp;
+	jme_resume_rx(jme);
 }
 
 static void