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Subject: Re: [PATCH v2] xen-netfront: Fix Rx stall during network stress and
 OOM
To: Boris Ostrovsky <boris.ostrovsky@oracle.com>
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CC: <linux-kernel@vger.kernel.org>, David Miller <davem@davemloft.net>,
        <netdev@vger.kernel.org>, Wei Liu <wei.liu2@citrix.com>,
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From: Vineeth Remanan Pillai <vineethp@amazon.com>
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Date: Mon, 30 Jan 2017 09:13:57 -0800
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On 01/30/2017 09:06 AM, Boris Ostrovsky wrote:
> On 01/30/2017 11:47 AM, Vineeth Remanan Pillai wrote:
>
>>> 2. It tickles a latent bug during resume where the timer triggers
>>> before we re-connect. The trouble is that we now try to dereference
>>> queue->rx.sring which is NULL since we disconnect in
>>> netfront_resume(). (Curiously, I only observe it with 32-bit guests)
>> I think we may hit this bug after removing the timer as well. We call
>> RING_PUSH_REQUESTS_AND_CHECK_NOTIFY soon after, which also dereference
>> queue->rx.sring.
> If the timer is deleted in xennet_disconnect_backend() then why would
> anyone be pushing anything to the backend after that?
Sorry, I got the ordering wrong. Thanks for the clarification..

Thanks,
Vineeth