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.
> > + /* Running switches off */
> > + if ((old_state & VFIO_DEVICE_STATE_RUNNING) !=
> > + (state & VFIO_DEVICE_STATE_RUNNING) &&
>
> ((old_state ^ state) & VFIO_DEVICE_STATE_RUNNING) ?
It is not functionally the same, xor only tells if the bit changed, it
doesn't tell what the current value is, and this needs to know that it
changed to 1
> > + (old_state & VFIO_DEVICE_STATE_RUNNING)) {
> > + ret = mlx5vf_pci_quiesce_device(mvdev);
> > + if (ret)
> > + return ret;
> > + ret = mlx5vf_pci_freeze_device(mvdev);
> > + if (ret) {
> > + vmig->vfio_dev_state = VFIO_DEVICE_STATE_INVALID;
>
>
> No, the invalid states are specifically unreachable, the uAPI defines
> the error state for this purpose.
Indeed
> The states noted as invalid in the
> uAPI should be considered reserved at this point. If only there was a
> macro to set an error state... ;)
It should just assign a constant value, there is only one error state.
Jason
