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Date:   Tue, 28 Sep 2021 16:35:50 -0300
From:   Jason Gunthorpe <jgg@ziepe.ca>
To:     Alex Williamson <alex.williamson@redhat.com>
Cc:     Leon Romanovsky <leon@kernel.org>,
        Doug Ledford <dledford@redhat.com>,
        Yishai Hadas <yishaih@nvidia.com>,
        Bjorn Helgaas <bhelgaas@google.com>,
        "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Kirti Wankhede <kwankhede@nvidia.com>, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org,
        linux-rdma@vger.kernel.org, netdev@vger.kernel.org,
        Saeed Mahameed <saeedm@nvidia.com>,
        Cornelia Huck <cohuck@redhat.com>
Subject: Re: [PATCH mlx5-next 2/7] vfio: Add an API to check migration state
 transition validity
Message-ID: <20210928193550.GR3544071@ziepe.ca>
References: <cover.1632305919.git.leonro@nvidia.com>
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 <20210927164648.1e2d49ac.alex.williamson@redhat.com>
 <20210927231239.GE3544071@ziepe.ca>
 <20210928131958.61b3abec.alex.williamson@redhat.com>
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On Tue, Sep 28, 2021 at 01:19:58PM -0600, Alex Williamson wrote:

> In defining the device state, we tried to steer away from defining it
> in terms of the QEMU migration API, but rather as a set of controls
> that could be used to support that API to leave us some degree of
> independence that QEMU implementation might evolve.

That is certainly a different perspective, it would have been
better to not express this idea as a FSM in that case...

So each state in mlx5vf_pci_set_device_state() should call the correct
combination of (un)freeze, (un)quiesce and so on so each state
reflects a defined operation of the device?

Jason