src/patches/suse-2.6.27.31/patches.arch/s390-10-07-zfcp_refc_work_inflight.patch

   1 From: Gerald Schaefer <geraldsc@de.ibm.com>
   2 Subject: zfcp: fix queue, scheduled work processing.
   3 References: bnc#482818,LTC#51963
   4
   5 Symptom:     A nonexisting device might get referenced by a task.
   6 Problem:     An asynchronous scheduled work might get executed
   7              at a time the originating device is already removed.
   8 Solution:    Secure all devices by proper ref-counting and cancel
   9              outstanding work before device-removal.
  10
  11 Acked-by: John Jolly <jjolly@suse.de>
  12 ---
  13  drivers/s390/scsi/zfcp_aux.c |    1 +
  14  drivers/s390/scsi/zfcp_erp.c |   10 +++++++---
  15  2 files changed, 8 insertions(+), 3 deletions(-)
  16
  17 --- a/drivers/s390/scsi/zfcp_aux.c
  18 +++ b/drivers/s390/scsi/zfcp_aux.c
  19 @@ -553,6 +553,7 @@ void zfcp_adapter_dequeue(struct zfcp_ad
  20
  21         cancel_work_sync(&adapter->scan_work);
  22         cancel_work_sync(&adapter->stat_work);
  23 +       cancel_delayed_work_sync(&adapter->nsp.work);
  24         zfcp_adapter_scsi_unregister(adapter);
  25         sysfs_remove_group(&adapter->ccw_device->dev.kobj,
  26                            &zfcp_sysfs_adapter_attrs);
  27 --- a/drivers/s390/scsi/zfcp_erp.c
  28 +++ b/drivers/s390/scsi/zfcp_erp.c
  29 @@ -859,7 +859,7 @@ void zfcp_erp_port_strategy_open_lookup(
  30         port->erp_action.step = ZFCP_ERP_STEP_NAMESERVER_LOOKUP;
  31         if (retval)
  32                 zfcp_erp_notify(&port->erp_action, ZFCP_ERP_FAILED);
  33 -
  34 +       zfcp_port_put(port);
  35  }
  36
  37  static int zfcp_erp_port_strategy_open_common(struct zfcp_erp_action *act)
  38 @@ -875,7 +875,10 @@ static int zfcp_erp_port_strategy_open_c
  39                 if (fc_host_port_type(adapter->scsi_host) == FC_PORTTYPE_PTP)
  40                         return zfcp_erp_open_ptp_port(act);
  41                 if (!(p_status & ZFCP_STATUS_PORT_DID_DID)) {
  42 -                       queue_work(zfcp_data.work_queue, &port->gid_pn_work);
  43 +                       zfcp_port_get(port);
  44 +                       if (!queue_work(zfcp_data.work_queue,
  45 +                                       &port->gid_pn_work))
  46 +                               zfcp_port_put(port);
  47                         return ZFCP_ERP_CONTINUES;
  48                 }
  49         case ZFCP_ERP_STEP_NAMESERVER_LOOKUP:
  50 @@ -1218,7 +1221,8 @@ static void zfcp_erp_schedule_work(struc
  51         atomic_set_mask(ZFCP_STATUS_UNIT_SCSI_WORK_PENDING, &unit->status);
  52         INIT_WORK(&p->work, zfcp_erp_scsi_scan);
  53         p->unit = unit;
  54 -       queue_work(zfcp_data.work_queue, &p->work);
  55 +       if (!queue_work(zfcp_data.work_queue, &p->work))
  56 +               zfcp_unit_put(unit);
  57  }
  58
  59  static void zfcp_erp_action_cleanup(struct zfcp_erp_action *act, int result)