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Date:   Wed, 10 Mar 2021 07:56:39 +0000
From:   Christoph Hellwig <hch@infradead.org>
To:     Alex Williamson <alex.williamson@redhat.com>
Cc:     cohuck@redhat.com, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org, jgg@nvidia.com, peterx@redhat.com
Subject: Re: [PATCH v1 07/14] vfio: Add a device notifier interface
Message-ID: <20210310075639.GB662265@infradead.org>
References: <161523878883.3480.12103845207889888280.stgit@gimli.home>
 <161524010999.3480.14282676267275402685.stgit@gimli.home>
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On Mon, Mar 08, 2021 at 02:48:30PM -0700, Alex Williamson wrote:
> Using a vfio device, a notifier block can be registered to receive
> select device events.  Notifiers can only be registered for contained
> devices, ie. they are available through a user context.  Registration
> of a notifier increments the reference to that container context
> therefore notifiers must minimally respond to the release event by
> asynchronously removing notifiers.

Notifiers generally are a horrible multiplexed API.  Can't we just
add a proper method table for the intended communication channel?