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From:   Alvaro Karsz <alvaro.karsz@solid-run.com>
To:     "Michael S. Tsirkin" <mst@redhat.com>
CC:     Jason Wang <jasowang@redhat.com>,
        "davem@davemloft.net" <davem@davemloft.net>,
        "edumazet@google.com" <edumazet@google.com>,
        "kuba@kernel.org" <kuba@kernel.org>,
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        "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
Thread-Topic: [PATCH net] virtio-net: reject small vring sizes
Thread-Index: AQHZcDeGnH5xR2OGlkuo4s6jvhNMC68uIjT9gABGFgCAAG90AIAAMSwAgAABjzCAAARBAIAABATIgAAENICAAAM4M4AAIQOAgAALfyE=
Date:   Mon, 17 Apr 2023 10:04:56 +0000
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> > So, what do you think, we should fix virtio-net to work with smaller ri=
ngs? we should fail probe?=0A=
> >=0A=
> > I think that since this never came up until now, there is no big demand=
 to such small rings.=0A=
> =0A=
> The worry is that once we start failing probe there's just a tiny chance=
=0A=
> hosts begin to rely on us failing probe then we won't be able to fix it.=
=0A=
> So it depends on the size of the patch I think. So far it seems small eno=
ugh=0A=
> that wasting code on failing probe isn't worth it.=0A=
> =0A=
=0A=
I see your point.=0A=
Regardless, we'll need to fail probe in some cases.=0A=
ring size of 1 for example (if I'm not mistaken)=0A=
control vq even needs a bigger ring.=0A=
=0A=
Maybe we can fix virtnet to allow smaller rings + fail probe in some cases,=
 all in the same patch/patchset.=