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Date:   Wed, 28 Dec 2022 14:35:58 +0800
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Subject: Re: [PATCH 4/4] virtio-net: sleep instead of busy waiting for cvq
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To:     "Michael S. Tsirkin" <mst@redhat.com>
Cc:     Xuan Zhuo <xuanzhuo@linux.alibaba.com>, netdev@vger.kernel.org,
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From:   Jason Wang <jasowang@redhat.com>
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在 2022/12/27 17:31, Michael S. Tsirkin 写道:
> On Tue, Dec 27, 2022 at 05:17:20PM +0800, Jason Wang wrote:
>>>>> In particular, we will also directly break the device.
>>>> It's kind of hardening for malicious devices.
>>> ATM no amount of hardening can prevent a malicious hypervisor from
>>> blocking the guest. Recovering when a hardware device is broken would be
>>> nice but I think if we do bother then we should try harder to recover,
>>> such as by driving device reset.
>>
>> Probably, but as discussed in another thread, it needs co-operation in the
>> upper layer (networking core).
> To track all state? Yea, maybe. For sure it's doable just in virtio,
> but if you can find 1-2 other drivers that do this internally
> then factoring this out to net core will likely be accepted.


One thing that might be useful is to reuse tx_timeout() but current 
virtio-net doesn't do more than a simple warning (other drivers may try 
to reset).

So I would leave it for future investigation.

Thanks


>