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Date: Fri, 1 Feb 2019 10:09:08 +0100
From: Stefano Garzarella <sgarzare@redhat.com>
Message-ID: <20190201090908.vtb2u5pwvouej7ei@steredhat>
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Subject: Re: [Qemu-devel] [PATCH v2 2/5] virtio-blk: add "discard-wzeroes"
 boolean property
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To: Stefan Hajnoczi <stefanha@redhat.com>
Cc: qemu-devel@nongnu.org, Kevin Wolf <kwolf@redhat.com>, Eduardo Habkost <ehabkost@redhat.com>, Laurent Vivier <lvivier@redhat.com>, Paolo Bonzini <pbonzini@redhat.com>, Max Reitz <mreitz@redhat.com>, "Dr . David Alan Gilbert" <dgilbert@redhat.com>, Marcel Apfelbaum <marcel.apfelbaum@gmail.com>, Thomas Huth <thuth@redhat.com>, qemu-block@nongnu.org, "Michael S. Tsirkin" <mst@redhat.com>

On Fri, Feb 01, 2019 at 12:29:28PM +0800, Stefan Hajnoczi wrote:
> On Thu, Jan 31, 2019 at 04:19:11PM +0100, Stefano Garzarella wrote:
> > In order to avoid migration issues, we enable DISCARD and
> > WRITE ZEROES features only for machine type >= 4.0
> 
> Please use two separate properties that correspond to the
> VIRTIO_BLK_F_DISCARD and VIRTIO_BLK_F_WRITE_ZEROES virtio-blk feature
> bits.

Okay.
As Michael suggested, what do you think if I use a similar approach of
virtio-net, adding an host_features variable and setting a corresponding
feature bit?

Thanks,
Stefano