Re: [lock validator] drivers/net/8139too.c: deadlock?

[Jeff Garzik]

Herbert Xu wrote:
> You've got it.
>
> rx_poll => rtl8139_rx => netif_receive_skb => ... => tcp_v4_rcv
>
> In fact once we're at netif_receive_skb it's easy to see how we'll grab
> xmit_lock again.
>
> Prescription: Move TX timeout handling into a work queue.


This was my recommendation as well.

Using a work queue not only solves this locking problem, but it also 
enables the possibility of sleeping, a common operation during the 
hardware resets that often occur during ->tx_timeout()

Anyone who wants to make this change in a driver, don't forget that this 
could race with other operations, notably dev->stop() or suspend.

	Jeff


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