SCSI: isci: Fix a race condition in the SSP task management path

commit 96f15f29038e58e1b0a96483e2b369ff446becf1 upstream.

This commit fixes a race condition in the isci driver abort task and SSP
device task management path.  The race is caused when an I/O termination
in the SCU hardware is necessary because of an SSP target timeout condition,
and the check of the I/O end state races against the HW-termination-driven
end state.  The failure of the race meant that no TMF was sent to the device
to clean-up the pending I/O.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Reviewed-by: Lukasz Dorau <lukasz.dorau@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 6 insertions, 3 deletions

diff --git a/drivers/scsi/isci/task.c b/drivers/scsi/isci/task.c
index 9bb020ac089c..0d30ca849e8f 100644
--- a/drivers/scsi/isci/task.c
+++ b/drivers/scsi/isci/task.c
@@ -491,6 +491,7 @@ int isci_task_abort_task(struct sas_task *task)
         struct isci_tmf           tmf;
         int                       ret = TMF_RESP_FUNC_FAILED;
         unsigned long             flags;
+        int                       target_done_already = 0;
 
         /* Get the isci_request reference from the task.  Note that
          * this check does not depend on the pending request list
@@ -505,9 +506,11 @@ int isci_task_abort_task(struct sas_task *task)
         /* If task is already done, the request isn't valid */
         if (!(task->task_state_flags & SAS_TASK_STATE_DONE) &&
             (task->task_state_flags & SAS_TASK_AT_INITIATOR) &&
-            old_request)
+            old_request) {
                 idev = isci_get_device(task->dev->lldd_dev);
-
+                target_done_already = test_bit(IREQ_COMPLETE_IN_TARGET,
+                                               &old_request->flags);
+        }
         spin_unlock(&task->task_state_lock);
         spin_unlock_irqrestore(&ihost->scic_lock, flags);
 
@@ -561,7 +564,7 @@ int isci_task_abort_task(struct sas_task *task)
 
         if (task->task_proto == SAS_PROTOCOL_SMP ||
             sas_protocol_ata(task->task_proto) ||
-            test_bit(IREQ_COMPLETE_IN_TARGET, &old_request->flags) ||
+            target_done_already ||
             test_bit(IDEV_GONE, &idev->flags)) {
 
                 spin_unlock_irqrestore(&ihost->scic_lock, flags);