Re: [PATCH net] iavf: Do not restart Tx queues after reset task failure

From: Leon Romanovsky
Date: Wed Nov 09 2022 - 13:20:46 EST


On Tue, Nov 08, 2022 at 11:25:02AM +0100, Ivan Vecera wrote:
> After commit aa626da947e9 ("iavf: Detach device during reset task")
> the device is detached during reset task and re-attached at its end.
> The problem occurs when reset task fails because Tx queues are
> restarted during device re-attach and this leads later to a crash.

<...>

> + if (netif_running(netdev)) {
> + /* Close device to ensure that Tx queues will not be started
> + * during netif_device_attach() at the end of the reset task.
> + */
> + rtnl_lock();
> + dev_close(netdev);
> + rtnl_unlock();
> + }

Sorry for my naive question, I see this pattern a lot (including RDMA),
so curious. Everyone checks netif_running() outside of rtnl_lock, while
dev_close() changes state bit __LINK_STATE_START. Shouldn't rtnl_lock()
placed before netif_running()?

Thanks

> +
> dev_err(&adapter->pdev->dev, "failed to allocate resources during reinit\n");
> reset_finish:
> rtnl_lock();
> --
> 2.37.4
>