Re: [PATCH] as i/o hang with aacraid driver 2.6.0-test1

[Nick Piggin <piggin@cyberone.com.au>]

Thanks Mark, great. It looks fine.


>Daniel McNeil and I have been debugging a hang with the aacraid driver
>using the as I/O scheduler.  We found that scsi_request_fn would
>de-queue a request and later re-queued it.  This left the
>as_data->nr_dispatched variable in an inconsistent state (it was never
>being decremented back to zero).  We added a call to
>elv_completed_request to clean up the state before re-adding the
>request.  This has fixed our hang problem.  The linux-scsi list is being
>copied for review of the scsi_lib.c change.
>
>===== drivers/scsi/scsi_lib.c 1.99 vs edited =====
>--- 1.99/drivers/scsi/scsi_lib.c	Sun Jun 29 18:14:44 2003
>+++ edited/drivers/scsi/scsi_lib.c	Tue Jul 15 15:47:45 2003
>@@ -1215,6 +1215,7 @@
> 	spin_lock_irq(q->queue_lock);
> 	if (blk_rq_tagged(req))
> 		blk_queue_end_tag(q, req);
>+	elv_completed_request(q, req);
> 	__elv_add_request(q, req, 0, 0);
> 	sdev->device_busy--;
> 	if(sdev->device_busy == 0)
>
>  
>