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Date:   Mon, 17 Apr 2023 02:20:16 -0400
From:   "Michael S. Tsirkin" <mst@redhat.com>
To:     Jason Wang <jasowang@redhat.com>
Cc:     Alvaro Karsz <alvaro.karsz@solid-run.com>,
        "davem@davemloft.net" <davem@davemloft.net>,
        "edumazet@google.com" <edumazet@google.com>,
        "kuba@kernel.org" <kuba@kernel.org>,
        "pabeni@redhat.com" <pabeni@redhat.com>,
        "virtualization@lists.linux-foundation.org" 
        <virtualization@lists.linux-foundation.org>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH net] virtio-net: reject small vring sizes
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References: <20230416074607.292616-1-alvaro.karsz@solid-run.com>
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On Mon, Apr 17, 2023 at 11:24:16AM +0800, Jason Wang wrote:
> On Mon, Apr 17, 2023 at 4:45 AM Michael S. Tsirkin <mst@redhat.com> wrote:
> >
> > On Sun, Apr 16, 2023 at 04:54:57PM +0000, Alvaro Karsz wrote:
> > > After further consideration, other virtio drivers need a minimum limit to the vring size too.
> > >
> > > Maybe this can be more general, for example a new virtio_driver callback that is called (if implemented) during virtio_dev_probe, before drv->probe.
> > >
> > > What do you think?
> > >
> > > Thanks,
> > > Alvaro
> >
> > Let's start with what you did here, when more than 2 drivers do it we'll
> > move it to core.
> 
> I wonder how hard it is to let virtio support small vring size?
> 
> Thanks

Actually, I think that all you need to do is disable NETIF_F_SG,
and things will work, no?
Alvaro, can you try?


> >
> > --
> > MST
> >