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Date:   Mon, 26 Jul 2021 20:09:06 -0300
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     Cornelia Huck <cohuck@redhat.com>
Cc:     Christoph Hellwig <hch@lst.de>,
        Kirti Wankhede <kwankhede@nvidia.com>,
        Alex Williamson <alex.williamson@redhat.com>,
        kvm@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2] vfio/mdev: don't warn if ->request is not set
Message-ID: <20210726230906.GD1721383@nvidia.com>
References: <20210726143524.155779-1-hch@lst.de>
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On Mon, Jul 26, 2021 at 07:07:04PM +0200, Cornelia Huck wrote:

> But I wonder why nobody else implements this? Lack of surprise removal?

The only implementation triggers an eventfd that seems to be the same
eventfd as the interrupt..

Do you know how this works in userspace? I'm surprised that the
interrupt eventfd can trigger an observation that the kernel driver
wants to be unplugged?

Jason