ehea: fix race condition

When ehea_stop is called the function
cancel_work_sync(&port->reset_task) is used to ensure
that the reset task is not running anymore. We need an
additional flag to ensure that it can not be scheduled
after this call again for a certain time.

Signed-off-by: Jan-Bernd Themann <themann@de.ibm.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

1 files changed, 12 insertions, 5 deletions

diff --git a/drivers/net/ehea/ehea_main.c b/drivers/net/ehea/ehea_main.c
index 6ebcb221cd5e..49ba6a9a7b06 100644
--- a/drivers/net/ehea/ehea_main.c
+++ b/drivers/net/ehea/ehea_main.c
@@ -138,6 +138,12 @@ void ehea_dump(void *adr, int len, char *msg)
 	}
 }
 
+void ehea_schedule_port_reset(struct ehea_port *port)
+{
+	if (!test_bit(__EHEA_DISABLE_PORT_RESET, &port->flags))
+		schedule_work(&port->reset_task);
+}
+
 static void ehea_update_firmware_handles(void)
 {
 	struct ehea_fw_handle_entry *arr = NULL;
@@ -588,7 +594,7 @@ static int ehea_treat_poll_error(struct ehea_port_res *pr, int rq,
 				   "Resetting port.", pr->qp->init_attr.qp_nr);
 			ehea_dump(cqe, sizeof(*cqe), "CQE");
 		}
-		schedule_work(&pr->port->reset_task);
+		ehea_schedule_port_reset(pr->port);
 		return 1;
 	}
 
@@ -766,7 +772,7 @@ static struct ehea_cqe *ehea_proc_cqes(struct ehea_port_res *pr, int my_quota)
 			ehea_error("Send Completion Error: Resetting port");
 			if (netif_msg_tx_err(pr->port))
 				ehea_dump(cqe, sizeof(*cqe), "Send CQE");
-			schedule_work(&pr->port->reset_task);
+			ehea_schedule_port_reset(pr->port);
 			break;
 		}
 
@@ -886,7 +892,7 @@ static irqreturn_t ehea_qp_aff_irq_handler(int irq, void *param)
 		eqe = ehea_poll_eq(port->qp_eq);
 	}
 
-	schedule_work(&port->reset_task);
+	ehea_schedule_port_reset(port);
 
 	return IRQ_HANDLED;
 }
@@ -2606,13 +2612,14 @@ static int ehea_stop(struct net_device *dev)
 	if (netif_msg_ifdown(port))
 		ehea_info("disabling port %s", dev->name);
 
+	set_bit(__EHEA_DISABLE_PORT_RESET, &port->flags);
 	cancel_work_sync(&port->reset_task);
-
 	mutex_lock(&port->port_lock);
 	netif_stop_queue(dev);
 	port_napi_disable(port);
 	ret = ehea_down(dev);
 	mutex_unlock(&port->port_lock);
+	clear_bit(__EHEA_DISABLE_PORT_RESET, &port->flags);
 	return ret;
 }
 
@@ -2942,7 +2949,7 @@ static void ehea_tx_watchdog(struct net_device *dev)
 
 	if (netif_carrier_ok(dev) &&
 	    !test_bit(__EHEA_STOP_XFER, &ehea_driver_flags))
-		schedule_work(&port->reset_task);
+		ehea_schedule_port_reset(port);
 }
 
 int ehea_sense_adapter_attr(struct ehea_adapter *adapter)