Re: [PATCH mlx5-next 2/7] vfio: Add an API to check migration state transition validity

From: Jason Gunthorpe
Date: Wed Sep 29 2021 - 12:14:43 EST


On Wed, Sep 29, 2021 at 06:28:44PM +0300, Max Gurtovoy wrote:

> > So you have a device that's actively modifying its internal state,
> > performing I/O, including DMA (thereby dirtying VM memory), all while
> > in the _STOP state? And you don't see this as a problem?
>
> I don't see how is it different from vfio-pci situation.

vfio-pci provides no way to observe the migration state. It isn't
"000b"

> Maybe we need to rename STOP state. We can call it READY or LIVE or
> NON_MIGRATION_STATE.

It was a poor choice to use 000b as stop, but it doesn't really
matter. The mlx5 driver should just pre-init this readable to running.

Jason