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Date:   Thu, 26 Sep 2019 21:34:23 +0800
From:   Tiwei Bie <tiwei.bie@intel.com>
To:     "Michael S. Tsirkin" <mst@redhat.com>
Cc:     jasowang@redhat.com, alex.williamson@redhat.com,
        maxime.coquelin@redhat.com, linux-kernel@vger.kernel.org,
        kvm@vger.kernel.org, virtualization@lists.linux-foundation.org,
        netdev@vger.kernel.org, dan.daly@intel.com,
        cunming.liang@intel.com, zhihong.wang@intel.com,
        lingshan.zhu@intel.com
Subject: Re: [PATCH] vhost: introduce mdev based hardware backend
Message-ID: <20190926133423.GA15574@___>
References: <20190926045427.4973-1-tiwei.bie@intel.com>
 <20190926042156-mutt-send-email-mst@kernel.org>
 <20190926131439.GA11652@___>
 <20190926091945-mutt-send-email-mst@kernel.org>
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On Thu, Sep 26, 2019 at 09:26:22AM -0400, Michael S. Tsirkin wrote:
> On Thu, Sep 26, 2019 at 09:14:39PM +0800, Tiwei Bie wrote:
> > > 4. Does device need to limit max ring size?
> > > 5. Does device need to limit max number of queues?
> > 
> > I think so. It's helpful to have ioctls to report the max
> > ring size and max number of queues.
> 
> Also, let's not repeat the vhost net mistakes, let's lock
> everything to the order required by the virtio spec,
> checking status bits at each step.
> E.g.:
> 	set backend features
> 	set features
> 	detect and program vqs
> 	enable vqs
> 	enable driver
> 
> and check status at each step to force the correct order.
> e.g. don't allow enabling vqs after driver ok, etc

Got it. Thanks a lot!

Regards,
Tiwei

> 
> -- 
> MST