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From:   Alvaro Karsz <alvaro.karsz@solid-run.com>
To:     "Michael S. Tsirkin" <mst@redhat.com>
CC:     "jasowang@redhat.com" <jasowang@redhat.com>,
        "davem@davemloft.net" <davem@davemloft.net>,
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        "xuanzhuo@linux.alibaba.com" <xuanzhuo@linux.alibaba.com>
Subject: Re: [RFC PATCH net 2/3] virtio-net: allow usage of vrings smaller
 than MAX_SKB_FRAGS + 2
Thread-Topic: [RFC PATCH net 2/3] virtio-net: allow usage of vrings smaller
 than MAX_SKB_FRAGS + 2
Thread-Index: AQHZe2XXxDQ9u/7pQUe+LxobnBX4G69D4sMAgABG2xSAAQzMAIAAF+VB
Date:   Mon, 1 May 2023 11:59:42 +0000
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> First up to 4k should not be a problem. Even jumbo frames e.g. 9k=0A=
> is highly likely to succeed. And a probe time which is often boot=0A=
> even 64k isn't a problem ...=0A=
> =0A=
> Hmm. We could allocate large buffers at probe time. Reuse them and=0A=
> copy data over.=0A=
> =0A=
> IOW reusing  GOOD_COPY_LEN flow for this case.  Not yet sure how I feel=
=0A=
> about this. OTOH it removes the need for the whole feature blocking=0A=
> approach, does it not?=0A=
> WDYT?=0A=
> =0A=
=0A=
It could work..=0A=
=0A=
In order to remove completely the feature blocking approach, we'll need to =
let the control commands fail (as you mentioned in the other patch).=0A=
I'm not sure I like it, it means many warnings from virtnet..=0A=
And it means accepting features that we know for sure that are not going to=
 work.=0A=