Subject: Re: [PATCH net 3/9] virtio-net: fix page miscount during XDP
 linearizing
To: John Fastabend <john.fastabend@gmail.com>, mst@redhat.com,
        virtualization@lists.linux-foundation.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <1482503852-12438-1-git-send-email-jasowang@redhat.com>
 <1482503852-12438-4-git-send-email-jasowang@redhat.com>
 <585D48A7.3040701@gmail.com>
Cc: john.r.fastabend@intel.com
From: Jason Wang <jasowang@redhat.com>
Message-ID: <42cb7705-748a-f385-f5cd-e124e0f6e8e0@redhat.com>
Date: Mon, 26 Dec 2016 10:30:10 +0800
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On 2016年12月23日 23:54, John Fastabend wrote:
> On 16-12-23 06:37 AM, Jason Wang wrote:
>> We don't put page during linearizing, the would cause leaking when
>> xmit through XDP_TX or the packet exceeds PAGE_SIZE. Fix them by
>> put page accordingly. Also decrease the number of buffers during
>> linearizing to make sure caller can free buffers correctly when packet
>> exceeds PAGE_SIZE. With this patch, we won't get OOM after linearize
>> huge number of packets.
>>
>> Cc: John Fastabend <john.r.fastabend@intel.com>
>> Signed-off-by: Jason Wang <jasowang@redhat.com>
>> ---
> Thanks! looks good. By the way do you happen to have any actual
> configuration where this path is hit? I obviously didn't test this
> very long other than a quick test with my hacked vhost driver.
>
> Acked-by: John Fastabend <john.r.fastabend@intel.com>

Yes, I have. Just increase the MTU above 1500 for both virtio and tap 
and produce some traffic with size which will lead underestimated of rxbuf.

Thanks