src/patches/suse-2.6.27.25/patches.arch/s390-12-11-zfcp_fcp_port_handling.patch

   1 From: Gerald Schaefer <geraldsc@de.ibm.com>
   2 Subject: zfcp: Fix oops when port disappears
   3 References: bnc#487755,LTC#52844
   4
   5 Symptom:     Kernel oops when port disappears.
   6 Problem:     The zfcp_port might have been removed, while the FC
   7              fast_io_fail timer is still running and could trigger
   8              the terminate_rport_io callback.
   9 Solution:    Set the pointer to the zfcp_port to NULL and check
  10              accordingly before using it.
  11
  12 Acked-by: John Jolly <jjolly@suse.de>
  13 ---
  14  drivers/s390/scsi/zfcp_aux.c  |    3 +--
  15  drivers/s390/scsi/zfcp_fsf.c  |    4 ++++
  16  drivers/s390/scsi/zfcp_scsi.c |   25 +++++++++++++++++++------
  17  3 files changed, 24 insertions(+), 8 deletions(-)
  18
  19 --- a/drivers/s390/scsi/zfcp_aux.c
  20 +++ b/drivers/s390/scsi/zfcp_aux.c
  21 @@ -677,8 +677,7 @@ void zfcp_port_dequeue(struct zfcp_port
  22         list_del(&port->list);
  23         write_unlock_irq(&zfcp_data.config_lock);
  24         if (port->rport)
  25 -               fc_remote_port_delete(port->rport);
  26 -       port->rport = NULL;
  27 +               port->rport->dd_data = NULL;
  28         zfcp_adapter_put(port->adapter);
  29         sysfs_remove_group(&port->sysfs_device.kobj, &zfcp_sysfs_port_attrs);
  30         device_unregister(&port->sysfs_device);
  31 --- a/drivers/s390/scsi/zfcp_fsf.c
  32 +++ b/drivers/s390/scsi/zfcp_fsf.c
  33 @@ -175,12 +175,16 @@ static void zfcp_fsf_link_down_info_eval
  34                                          struct fsf_link_down_info *link_down)
  35  {
  36         struct zfcp_adapter *adapter = req->adapter;
  37 +       unsigned long flags;
  38
  39         if (atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED)
  40                 return;
  41
  42         atomic_set_mask(ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED, &adapter->status);
  43 +
  44 +       read_lock_irqsave(&zfcp_data.config_lock, flags);
  45         zfcp_scsi_schedule_rports_block(adapter);
  46 +       read_unlock_irqrestore(&zfcp_data.config_lock, flags);
  47
  48         if (!link_down)
  49                 goto out;
  50 --- a/drivers/s390/scsi/zfcp_scsi.c
  51 +++ b/drivers/s390/scsi/zfcp_scsi.c
  52 @@ -491,10 +491,12 @@ static void zfcp_set_rport_dev_loss_tmo(
  53   */
  54  static void zfcp_scsi_dev_loss_tmo_callbk(struct fc_rport *rport)
  55  {
  56 -       struct zfcp_port *port = rport->dd_data;
  57 +       struct zfcp_port *port;
  58
  59         write_lock_irq(&zfcp_data.config_lock);
  60 -       port->rport = NULL;
  61 +       port = rport->dd_data;
  62 +       if (port)
  63 +               port->rport = NULL;
  64         write_unlock_irq(&zfcp_data.config_lock);
  65  }
  66
  67 @@ -508,9 +510,18 @@ static void zfcp_scsi_dev_loss_tmo_callb
  68   */
  69  static void zfcp_scsi_terminate_rport_io(struct fc_rport *rport)
  70  {
  71 -       struct zfcp_port *port = rport->dd_data;
  72 +       struct zfcp_port *port;
  73
  74 -       zfcp_erp_port_reopen(port, 0, 152, NULL);
  75 +       write_lock_irq(&zfcp_data.config_lock);
  76 +       port = rport->dd_data;
  77 +       if (port)
  78 +               zfcp_port_get(port);
  79 +       write_unlock_irq(&zfcp_data.config_lock);
  80 +
  81 +       if (port) {
  82 +               zfcp_erp_port_reopen(port, 0, 152, NULL);
  83 +               zfcp_port_put(port);
  84 +       }
  85  }
  86
  87  static void zfcp_scsi_rport_register(struct zfcp_port *port)
  88 @@ -539,8 +550,10 @@ static void zfcp_scsi_rport_register(str
  89
  90  static void zfcp_scsi_rport_block(struct zfcp_port *port)
  91  {
  92 -       if (port->rport)
  93 -               fc_remote_port_delete(port->rport);
  94 +       struct fc_rport *rport = port->rport;
  95 +
  96 +       if (rport)
  97 +               fc_remote_port_delete(rport);
  98  }
  99
 100  void zfcp_scsi_schedule_rport_register(struct zfcp_port *port)