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Date: Fri, 27 Jan 2006 01:35:11 +0100
From: Francois Romieu <romieu@fr.zoreil.com>
To: Ingo Molnar <mingo@elte.hu>
Cc: Jeff Garzik <jgarzik@redhat.com>, linux-kernel@vger.kernel.org,
       Andrew Morton <akpm@osdl.org>, "David S. Miller" <davem@redhat.com>
Subject: Re: [lock validator] drivers/net/8139too.c: deadlock?
Message-ID: <20060127003511.GA10871@electric-eye.fr.zoreil.com>
References: <20060126224312.GA2779@elte.hu>
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Ingo Molnar <mingo@elte.hu> :
[...]
> i'm wondering, is this a genuine deadlock, or a false positive? The 
> dependency chain is quite complex, but looks realistic:
> 
>   -> #4 {&dev->xmit_lock}: [<c045294b>] dev_watchdog+0x1b/0xc0
>   -> #3 {&dev->queue_lock}: [<c0447154>] dev_queue_xmit+0x64/0x290
>   -> #2 {&((sk)->sk_lock.slock)}: [<c043eb66>] sk_clone+0x66/0x200
>   -> #1 {&((sk)->sk_lock.slock)}: [<c047a116>] tcp_v4_rcv+0x726/0x9d0
>   -> #0 {&tp->rx_lock}: [<c033e460>] rtl8139_tx_timeout+0x110/0x1f0

It looks like watchdog racing against rx_poll (which should/can not
happen). Do you have something specific in mind ?

--
Ueimor