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Date: Thu, 6 Mar 2025 10:21:46 -0800
From: Jakub Kicinski <kuba@kernel.org>
To: Joe Damato <jdamato@fastly.com>
Cc: netdev@vger.kernel.org, mkarsten@uwaterloo.ca,
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Subject: Re: [PATCH net-next v5 3/4] virtio-net: Map NAPIs to queues
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On Thu, 6 Mar 2025 09:00:02 -0800 Joe Damato wrote:
> +                *   - wrap all of the work in a lock (perhaps vi->refill_lock?)
> +                *   - check netif_running() and return early to avoid a race
> +                */

probably netdev instance lock is better here, as it will also
protect the return value of netif_running(). IOW we need to
base the "is the device up" test on some state that's protected
by the lock we take.