src/patches/suse-2.6.27.31/patches.fixes/libiscsi-fix-locking-in-eh_device_reset

   1 From: Mike Christie <michaelc@cs.wisc.edu>
   2 Date: Wed Sep 24 11:46:15 2008 -0500
   3 Subject: fix locking in iscsi_eh_device_reset
   4 X-Git: a343914831a8e29d89af3b26495ab1136a9e3153
   5 References: bnc#498369
   6
   7 We must be using the bh spin locking functions in
   8 iscsi_eh_device_reset becuase the session lock interacts with
   9 a thread and softirq.
  10
  11 This patch also fixes up a bogus comment and check in fail_command,
  12 because no one drops the lock (bnx2i did but it is not going
  13 upstream yet and there were other refcount changes for that).
  14
  15 Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
  16 Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
  17 Signed-off-by: Hannes Reinecke <hare@suse.de>
  18
  19 ---
  20  drivers/scsi/libiscsi.c |    9 ++-------
  21  1 file changed, 2 insertions(+), 7 deletions(-)
  22
  23 --- a/drivers/scsi/libiscsi.c
  24 +++ b/drivers/scsi/libiscsi.c
  25 @@ -413,11 +413,6 @@ static void fail_command(struct iscsi_co
  26                 conn->session->queued_cmdsn--;
  27         else
  28                 conn->session->tt->cleanup_task(conn, task);
  29 -       /*
  30 -        * Check if cleanup_task dropped the lock and the command completed,
  31 -        */
  32 -       if (!task->sc)
  33 -               return;
  34
  35         sc->result = err;
  36         if (!scsi_bidi_cmnd(sc))
  37 @@ -1839,10 +1834,10 @@ int iscsi_eh_device_reset(struct scsi_cm
  38
  39         iscsi_suspend_tx(conn);
  40
  41 -       spin_lock(&session->lock);
  42 +       spin_lock_bh(&session->lock);
  43         fail_all_commands(conn, sc->device->lun, DID_ERROR);
  44         conn->tmf_state = TMF_INITIAL;
  45 -       spin_unlock(&session->lock);
  46 +       spin_unlock_bh(&session->lock);
  47
  48         iscsi_start_tx(conn);
  49         goto done;