Re: [PATCH v2] xen-netfront: Fix Rx stall during network stress and OOM

From: Vineeth Remanan Pillai
Date: Mon Jan 30 2017 - 12:14:07 EST



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