On Mon, 21 Jan 2019 09:54:09 -0500 Farhan Ali <alifm@xxxxxxxxxxxxx> wrote: > This check is unecessary as we already have the vfio state machine > to handle I/O requests. > > On the other hand, this check returns incorrect information to > userspace if the state of the subchannel is not idle. For example > if the state is busy and new I/O request comes in, this will return > an EACCES, whereas we should return EBUSY. > > Signed-off-by: Farhan Ali <alifm@xxxxxxxxxxxxx> > --- > drivers/s390/cio/vfio_ccw_ops.c | 2 -- > 1 file changed, 2 deletions(-) > > diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c > index f673e10..3fdcc6d 100644 > --- a/drivers/s390/cio/vfio_ccw_ops.c > +++ b/drivers/s390/cio/vfio_ccw_ops.c > @@ -193,8 +193,6 @@ static ssize_t vfio_ccw_mdev_write(struct mdev_device *mdev, > return -EINVAL; > > private = dev_get_drvdata(mdev_parent_dev(mdev)); > - if (private->state != VFIO_CCW_STATE_IDLE) > - return -EACCES; > > region = private->io_region; > if (copy_from_user((void *)region + *ppos, buf, count)) Hm, the patchset for halt/clear handling I recently posted changes this to a check for NOT_OPER || STANDBY. What do you think of that option?
