[PATCH 1/3] xen/blkback: Don't trust the handle from the frontend.

[Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>]

The 'handle' is the device that the request is from. For the life-time
of the ring we copy it from a request to a response so that the frontend
is not surprised by it. But we do not need it - when we start processing
I/Os we have our own 'struct phys_req' which has only most essential
information about the request. In fact the 'vbd_translate' ends up
over-writing the preq.dev with a value from the backend.

This assignment of preq.dev with the 'handle' value is superfluous
so lets not do it.

Cc: stable@vger.kernel.org
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
---
 drivers/block/xen-blkback/blkback.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c
index 742871d..2de3da9 100644
--- a/drivers/block/xen-blkback/blkback.c
+++ b/drivers/block/xen-blkback/blkback.c
@@ -890,7 +890,6 @@ static int dispatch_rw_block_io(struct xen_blkif *blkif,
 		goto fail_response;
 	}
 
-	preq.dev           = req->u.rw.handle;
 	preq.sector_number = req->u.rw.sector_number;
 	preq.nr_sects      = 0;
 
-- 
1.8.0.2