Re: [PATCH] 2.6.0 NBD driver: remove send/recieve race for request

[Jens Axboe]

On Fri, Aug 08 2003, Lou Langholtz wrote:
> >@@ -499,12 +508,14 @@ static void do_nbd_request(request_queue
> >					lo->disk->disk_name);
> >			spin_lock(&lo->queue_lock);
> >			list_del_init(&req->queuelist);
> >+			req->ref_count--;
> >			spin_unlock(&lo->queue_lock);
> >			nbd_end_request(req);
> >			spin_lock_irq(q->queue_lock);
> >			continue;
> >		}
> >
> >+		req->ref_count--;
> >		spin_lock_irq(q->queue_lock);
> >
> Since ref_count isn't atomic, shouldn't ref_count only be changed while 
> the queue_lock is held???

Indeed, needs to be done after regrabbing the lock.

-- 
Jens Axboe

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