Re: [Xen-devel] [PATCH 3/3] xen/blkback: Check for insane amounts of request on the ring.

David Vrabel
2013-01-28T11:38:59Z

On 25/01/13 18:43, Konrad Rzeszutek Wilk wrote:
>
> Check that the ring does not have an insane amount of requests
> (more than there could fit on the ring).
[...]
> --- a/drivers/block/xen-blkback/blkback.c
> +++ b/drivers/block/xen-blkback/blkback.c
[...]
> @@ -415,8 +415,12 @@ int xen_blkif_schedule(void *arg)
> blkif->waiting_reqs = 0;
> smp_mb(); /* clear flag *before* checking for work */
>
> - if (do_block_io_op(blkif))
> + rc = do_block_io_op(blkif);
> + if (rc > 0)
> blkif->waiting_reqs = 1;
> + if (rc == -EACCES)
> + wait_event_interruptible(blkif->shutdown_wq,
> + kthread_should_stop());

So if this happens then the backend silently stops processing any
further requests? I think it should print an error and disconnect from
the front end.

David