4.16-stable review patch. If anyone has any objections, please let me know.
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From: Cornelia Huck cohuck@redhat.com
[ Upstream commit 9851bc77e62499957567e7c39a5beba7d6de6296 ]
vfio-ccw only supports command mode for channel programs, not transport mode. User space is supposed to already take care of that and pass us command-mode ORBs only, but better make sure and return an error to the caller instead of trying to process tcws as ccws.
Reviewed-by: Dong Jia Shi bjsdjshi@linux.vnet.ibm.com Acked-by: Halil Pasic pasic@linux.vnet.ibm.com Signed-off-by: Cornelia Huck cohuck@redhat.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/s390/cio/vfio_ccw_fsm.c | 5 +++++ 1 file changed, 5 insertions(+)
--- a/drivers/s390/cio/vfio_ccw_fsm.c +++ b/drivers/s390/cio/vfio_ccw_fsm.c @@ -129,6 +129,11 @@ static void fsm_io_request(struct vfio_c if (scsw->cmd.fctl & SCSW_FCTL_START_FUNC) { orb = (union orb *)io_region->orb_area;
+ /* Don't try to build a cp if transport mode is specified. */ + if (orb->tm.b) { + io_region->ret_code = -EOPNOTSUPP; + goto err_out; + } io_region->ret_code = cp_init(&private->cp, mdev_dev(mdev), orb); if (io_region->ret_code)