[PULL 2/7] s390/cio: Set vfio-ccw FSM state before ioeventfd

Cornelia Huck
2019-06-03T10:50:33Z

Otherwise, the guest can believe it's okay to start another I/O
and bump into the non-idle state. This results in a cc=2 (with
the asynchronous CSCH/HSCH code) returned to the guest, which is
unfortunate since everything is otherwise working normally.

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Message-Id: <20190514234248.36203-3-farman@linux.ibm.com>
Reviewed-by: Farhan Ali <alifm@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
---
drivers/s390/cio/vfio_ccw_drv.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/s390/cio/vfio_ccw_drv.c b/drivers/s390/cio/vfio_ccw_drv.c
index ee8767f5845a..66a66ac1f3d1 100644
--- a/drivers/s390/cio/vfio_ccw_drv.c
+++ b/drivers/s390/cio/vfio_ccw_drv.c
@@ -95,11 +95,11 @@ static void vfio_ccw_sch_io_todo(struct work_struct *work)
memcpy(private->io_region->irb_area, irb, sizeof(*irb));
mutex_unlock(&private->io_mutex);

- if (private->io_trigger)
- eventfd_signal(private->io_trigger, 1);
-
if (private->mdev && is_final)
private->state = VFIO_CCW_STATE_IDLE;
+
+ if (private->io_trigger)
+ eventfd_signal(private->io_trigger, 1);
}

/*
--
2.20.1