On Sun, Oct 17, 2021 at 05:03:28PM +0300, Yishai Hadas wrote: > On 10/15/2021 11:59 PM, Alex Williamson wrote: > > On Fri, 15 Oct 2021 17:16:54 -0300 > > Jason Gunthorpe <jgg@xxxxxxxxxx> wrote: > > > > > On Fri, Oct 15, 2021 at 02:12:01PM -0600, Alex Williamson wrote: > > > > On Fri, 15 Oct 2021 16:59:37 -0300 > > > > Jason Gunthorpe <jgg@xxxxxxxxxx> wrote: > > > > > On Fri, Oct 15, 2021 at 01:48:20PM -0600, Alex Williamson wrote: > > > > > > > +static int mlx5vf_pci_set_device_state(struct mlx5vf_pci_core_device *mvdev, > > > > > > > + u32 state) > > > > > > > +{ > > > > > > > + struct mlx5vf_pci_migration_info *vmig = &mvdev->vmig; > > > > > > > + u32 old_state = vmig->vfio_dev_state; > > > > > > > + int ret = 0; > > > > > > > + > > > > > > > + if (vfio_is_state_invalid(state) || vfio_is_state_invalid(old_state)) > > > > > > > + return -EINVAL; > > > > > > if (!VFIO_DEVICE_STATE_VALID(old_state) || !VFIO_DEVICE_STATE_VALID(state)) > > > > > AFAICT this macro doesn't do what is needed, eg > > > > > > > > > > VFIO_DEVICE_STATE_VALID(0xF000) == true > > > > > > > > > > What Yishai implemented is at least functionally correct - states this > > > > > driver does not support are rejected. > > > > > > > > if (!VFIO_DEVICE_STATE_VALID(old_state) || !VFIO_DEVICE_STATE_VALID(state)) || (state & ~VFIO_DEVICE_STATE_MASK)) > > > > > > > > old_state is controlled by the driver and can never have random bits > > > > set, user state should be sanitized to prevent setting undefined bits. > > > In that instance let's just write > > > > > > old_state != VFIO_DEVICE_STATE_ERROR > > > > > > ? > > Not quite, the user can't set either of the other invalid states > > either. > > > OK so let's go with below as you suggested. > if (!VFIO_DEVICE_STATE_VALID(old_state) || > !VFIO_DEVICE_STATE_VALID(state) || > (state & ~VFIO_DEVICE_STATE_MASK)) > return -EINVAL; This is my preference: if (vmig->vfio_dev_state != VFIO_DEVICE_STATE_ERROR || !vfio_device_state_valid(state) || (state & !MLX5VF_SUPPORTED_DEVICE_STATES)) > diff --git a/include/linux/vfio.h b/include/linux/vfio.h > index b53a9557884a..37376dadca5a 100644 > +++ b/include/linux/vfio.h > @@ -15,6 +15,8 @@ > #include <linux/poll.h> > #include <uapi/linux/vfio.h> > > +static const int VFIO_DEVICE_STATE_ERROR = VFIO_DEVICE_STATE_SAVING | > + VFIO_DEVICE_STATE_RESUMING; Do not put static variables in header files Jason