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>

diff --git a/drivers/net/ehea/ehea.h b/drivers/net/ehea/ehea.h
index bf57e15..e01926b 100644 (file)
--- a/drivers/net/ehea/ehea.h
+++ b/drivers/net/ehea/ehea.h
@@ -40,7 +40,7 @@
 #include <asm/io.h>
 
 #define DRV_NAME       "ehea"
-#define DRV_VERSION    "EHEA_0091"
+#define DRV_VERSION    "EHEA_0092"
 
 /* eHEA capability flags */
 #define DLPAR_PORT_ADD_REM 1
@@ -478,6 +478,7 @@ struct ehea_port {
        int num_add_tx_qps;
        int num_mcs;
        int resets;
+       u64 flags;
        u64 mac_addr;
        u32 logical_port_id;
        u32 port_speed;
@@ -501,7 +502,8 @@ struct port_res_cfg {
 };
 
 enum ehea_flag_bits {
-       __EHEA_STOP_XFER
+       __EHEA_STOP_XFER,
+       __EHEA_DISABLE_PORT_RESET
 };
 
 void ehea_set_ethtool_ops(struct net_device *netdev);

diff --git a/drivers/net/ehea/ehea_main.c b/drivers/net/ehea/ehea_main.c
index 6ebcb22..49ba6a9 100644 (file)
--- 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)