xen/blkback: Don't trust the handle from the frontend.
authorKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Wed, 16 Jan 2013 16:36:23 +0000 (11:36 -0500)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sun, 3 Mar 2013 22:06:40 +0000 (06:06 +0800)
commitc93c85196e2c7001daa8a04b83a9d6dd4febfb59
tree64dab661cb1847cbf60d8017364ab5b2e1172d8d
parentf8cf1124a8f6cdd4ebc834ec3d848508e229e1d4
xen/blkback: Don't trust the handle from the frontend.

commit 01c681d4c70d64cb72142a2823f27c4146a02e63 upstream.

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.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/block/xen-blkback/blkback.c