1 files changed, 49 insertions, 4 deletions

diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
index c28a712fd4db..703eb6a88790 100644
--- a/drivers/scsi/libiscsi.c
+++ b/drivers/scsi/libiscsi.c
@@ -1919,10 +1919,11 @@ static int iscsi_has_ping_timed_out(struct iscsi_conn *conn)
 static enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *sc)
 {
         enum blk_eh_timer_return rc = BLK_EH_NOT_HANDLED;
-        struct iscsi_task *task = NULL;
+        struct iscsi_task *task = NULL, *running_task;
         struct iscsi_cls_session *cls_session;
         struct iscsi_session *session;
         struct iscsi_conn *conn;
+        int i;
 
         cls_session = starget_to_session(scsi_target(sc->device));
         session = cls_session->dd_data;
@@ -1947,8 +1948,15 @@ static enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *sc)
         }
 
         task = (struct iscsi_task *)sc->SCp.ptr;
-        if (!task)
+        if (!task) {
+                /*
+                 * Raced with completion. Just reset timer, and let it
+                 * complete normally
+                 */
+                rc = BLK_EH_RESET_TIMER;
                 goto done;
+        }
+
         /*
          * If we have sent (at least queued to the network layer) a pdu or
          * recvd one for the task since the last timeout ask for
@@ -1956,10 +1964,10 @@ static enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *sc)
          * we can check if it is the task or connection when we send the
          * nop as a ping.
          */
-        if (time_after_eq(task->last_xfer, task->last_timeout)) {
+        if (time_after(task->last_xfer, task->last_timeout)) {
                 ISCSI_DBG_EH(session, "Command making progress. Asking "
                              "scsi-ml for more time to complete. "
-                             "Last data recv at %lu. Last timeout was at "
+                             "Last data xfer at %lu. Last timeout was at "
                              "%lu\n.", task->last_xfer, task->last_timeout);
                 task->have_checked_conn = false;
                 rc = BLK_EH_RESET_TIMER;
@@ -1977,6 +1985,43 @@ static enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *sc)
                 goto done;
         }
 
+        for (i = 0; i < conn->session->cmds_max; i++) {
+                running_task = conn->session->cmds[i];
+                if (!running_task->sc || running_task == task ||
+                     running_task->state != ISCSI_TASK_RUNNING)
+                        continue;
+
+                /*
+                 * Only check if cmds started before this one have made
+                 * progress, or this could never fail
+                 */
+                if (time_after(running_task->sc->jiffies_at_alloc,
+                               task->sc->jiffies_at_alloc))
+                        continue;
+
+                if (time_after(running_task->last_xfer, task->last_timeout)) {
+                        /*
+                         * This task has not made progress, but a task
+                         * started before us has transferred data since
+                         * we started/last-checked. We could be queueing
+                         * too many tasks or the LU is bad.
+                         *
+                         * If the device is bad the cmds ahead of us on
+                         * other devs will complete, and this loop will
+                         * eventually fail starting the scsi eh.
+                         */
+                        ISCSI_DBG_EH(session, "Command has not made progress "
+                                     "but commands ahead of it have. "
+                                     "Asking scsi-ml for more time to "
+                                     "complete. Our last xfer vs running task "
+                                     "last xfer %lu/%lu. Last check %lu.\n",
+                                     task->last_xfer, running_task->last_xfer,
+                                     task->last_timeout);
+                        rc = BLK_EH_RESET_TIMER;
+                        goto done;
+                }
+        }
+
         /* Assumes nop timeout is shorter than scsi cmd timeout */
         if (task->have_checked_conn)
                 goto done;