On Fri, 5 Feb 2021 17:37:32 -0800 Edwin Peer wrote:
> Prevent netif_tx_disable() running concurrently with dev_watchdog() by
> taking the device global xmit lock. Otherwise, the recommended:
>
> netif_carrier_off(dev);
> netif_tx_disable(dev);
>
> driver shutdown sequence can happen after the watchdog has already
> checked carrier, resulting in possible false alarms. This is because
> netif_tx_lock() only sets the frozen bit without maintaining the locks
> on the individual queues.
>
> Fixes: c3f26a269c24 ("netdev: Fix lockdep warnings in multiqueue
> configurations.")
> Signed-off-by: Edwin Peer <edwin.p...@broadcom.com>
Reviewed-by: Jakub Kicinski <k...@kernel.org>
Even though using the dev->tx_global_lock as a barrier is not very
clean in itself the thinking is that this restores previous semantics
with deeper changes.
