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Date:   Wed, 10 Mar 2021 08:26:19 +0100
From:   Christoph Hellwig <hch@lst.de>
To:     Jason Gunthorpe <jgg@nvidia.com>
Cc:     Alex Williamson <alex.williamson@redhat.com>,
        Cornelia Huck <cohuck@redhat.com>,
        Jonathan Corbet <corbet@lwn.net>, kvm@vger.kernel.org,
        linux-doc@vger.kernel.org, "Raj, Ashok" <ashok.raj@intel.com>,
        Dan Williams <dan.j.williams@intel.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        Christoph Hellwig <hch@lst.de>,
        Leon Romanovsky <leonro@nvidia.com>,
        Max Gurtovoy <mgurtovoy@nvidia.com>,
        Tarun Gupta <targupta@nvidia.com>
Subject: Re: [PATCH 02/10] vfio: Split creation of a vfio_device into init
 and register ops
Message-ID: <20210310072619.GB2659@lst.de>
References: <0-v1-7355d38b9344+17481-vfio1_jgg@nvidia.com> <2-v1-7355d38b9344+17481-vfio1_jgg@nvidia.com>
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On Tue, Mar 09, 2021 at 05:38:44PM -0400, Jason Gunthorpe wrote:
> The pattern also makes it clear that vfio_register_group_dev() must be
> last in the sequence, as once it is called the core code can immediately
> start calling ops. The init/register gap is provided to allow for the
> driver to do setup before ops can be called and thus avoid races.

Yes, APIs that init and register together are generatelly a rather
bad idea.

Reviewed-by: Christoph Hellwig <hch@lst.de>