[PATCH] sbp2: fix another deadlock after disconnection

sbp2: fix another deadlock after disconnection

If there were commands enqueued but not completed before an SBP-2 unit
was unplugged (or an attempt to reconnect failed), knodemgrd or any
process which tried to remove the device would sleep uninterruptibly
in blk_execute_rq().  Therefore make sure that all commands are
completed when sbp2 retreats.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>

diff --git a/drivers/ieee1394/sbp2.c b/drivers/ieee1394/sbp2.c
index f7e18ccc5c0a28fbbbcbb541e765a8c581537dfa..82e3904458560ff941cb9b60fc309d8e182f298d 100644 (file)
--- a/drivers/ieee1394/sbp2.c
+++ b/drivers/ieee1394/sbp2.c
@@ -650,9 +650,15 @@ static int sbp2_remove(struct device *dev)
        if (!scsi_id)
                return 0;
 
-       /* Trigger shutdown functions in scsi's highlevel. */
-       if (scsi_id->scsi_host)
+       if (scsi_id->scsi_host) {
+               /* Get rid of enqueued commands if there is no chance to
+                * send them. */
+               if (!sbp2util_node_is_available(scsi_id))
+                       sbp2scsi_complete_all_commands(scsi_id, DID_NO_CONNECT);
+               /* scsi_remove_device() will trigger shutdown functions of SCSI
+                * highlevel drivers which would deadlock if blocked. */
                scsi_unblock_requests(scsi_id->scsi_host);
+       }
        sdev = scsi_id->sdev;
        if (sdev) {
                scsi_id->sdev = NULL;