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From:   Alvaro Karsz <alvaro.karsz@solid-run.com>
To:     "Michael S. Tsirkin" <mst@redhat.com>,
        Jason Wang <jasowang@redhat.com>
CC:     "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
Thread-Topic: [PATCH net] virtio-net: reject small vring sizes
Thread-Index: AQHZcDeGnH5xR2OGlkuo4s6jvhNMC68uIjT9gABGFgCAAG90AIAAMSwAgAABjzA=
Date:   Mon, 17 Apr 2023 06:38:43 +0000
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> Actually, I think that all you need to do is disable NETIF_F_SG,=0A=
> and things will work, no?=0A=
=0A=
I think that this is not so simple, if I understand correctly, by disabling=
 NETIF_F_SG we will never receive a chained skbs to transmit, but we still =
have more functionality to address, for example:=0A=
* The TX timeouts.=0A=
* Guest GSO/big MTU (without VIRTIO_NET_F_MRG_RXBUF?), we can't chain page =
size buffers anymore.=0A=
=0A=
> Alvaro, can you try?=0A=
=0A=
It won't matter at the moment, we'll get TX timeout after the first tx pack=
et, we need to address this part as well.=