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Date: Tue, 16 May 2023 12:36:35 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Jason Wang <jasowang@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>, davem@davemloft.net,
 edumazet@google.com, pabeni@redhat.com,
 virtualization@lists.linux-foundation.org, linux-kernel@vger.kernel.org,
 maxime.coquelin@redhat.com, alvaro.karsz@solid-run.com,
 eperezma@redhat.com, xuanzhuo@linux.alibaba.com, david.marchand@redhat.com,
 netdev <netdev@vger.kernel.org>
Subject: Re: [PATCH net-next V2 1/2] virtio-net: convert rx mode setting to
 use workqueue
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On Tue, 16 May 2023 12:17:50 +0800 Jason Wang wrote:
> > It's not reliable for other drivers but has been reliable for virtio.
> > I worry some software relied on this.  
> 
> It's probably fine since some device like vhost doesn't support this
> at all and we manage to survive for several years.
> 
> > You are making good points though ... could we get some
> > maintainer's feedback on this?  
> 
> That would be helpful. Jakub, any input on this?

AFAIU the question is whether .ndo_set_rx_mode needs to be reliable 
and instantaneous?  I haven't heard any complaints for it not being
immediate, and most 10G+ NICs do the config via a workqueue.

I even have an "intern task" to implement a workqueue in the core,
for this to save the boilerplate code in the drivers.