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From:   Alvaro Karsz <alvaro.karsz@solid-run.com>
To:     Xuan Zhuo <xuanzhuo@linux.alibaba.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>,
        "Michael S. Tsirkin" <mst@redhat.com>,
        Jason Wang <jasowang@redhat.com>
Subject: Re: [PATCH net] virtio-net: reject small vring sizes
Thread-Topic: [PATCH net] virtio-net: reject small vring sizes
Thread-Index: AQHZcDeGnH5xR2OGlkuo4s6jvhNMC68uIjT9gABGFgCAAG90AIAAMSwAgAABjzCAAAUmAIAABbXA
Date:   Mon, 17 Apr 2023 07:07:59 +0000
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> Why tx timeout without frags?=0A=
=0A=
Please see my response to Michael.=0A=
=0A=
> > * Guest GSO/big MTU (without VIRTIO_NET_F_MRG_RXBUF?), we can't chain p=
age size buffers anymore.=0A=
> =0A=
> =0A=
> Or, we disable the GUEST_GSO, HOST_GSO......=0A=
> =0A=
And disable VIRTIO_NET_F_MTU, quoting the spec:=0A=
"A driver SHOULD negotiate VIRTIO_NET_F_MTU if the device offers it."=0A=
=0A=
We can find a way around using buffers bigger than a page size like Michael=
 implied.=