From mboxrd@z Thu Jan  1 00:00:00 1970
From: Grant Grundler <grundler@parisc-linux.org>
Subject: Re: PATCHv3 2.6.17-rc5 tulip free_irq() called too late
Date: Wed, 14 Jun 2006 08:54:15 -0600
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Cc: Grant Grundler <grundler@parisc-linux.org>,
	Jeff Garzik <jgarzik@pobox.com>,
	Valerie Henson <val_henson@linux.intel.com>,
	Andrew Morton <akpm@osdl.org>, netdev@vger.kernel.org
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To: Kyle McMartin <kyle@mcmartin.ca>
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On Wed, Jun 14, 2006 at 09:05:06AM -0400, Kyle McMartin wrote:
> I think the correct sequence would be:
> 
> 	reset tulip interrupt mask
> 	flush posted write
> 
> 	synchronize irq			/* make sure we got 'em all */

> 	tulip_stop_rxtx			/* turn off dma */
> 	free irq			/* bye bye */
> 
> The synchronize irq guarantees we shouldn't see another irq
> generated by the card because it was held up somewhere.

Kyle,
syncronize_irq() only guarantees currently executing interrupt handler
completes before handing control back to the caller.
It does not guarantee IRQ signals still inflight are "flushed".
Remember that IRQ lines are a "sideband" signal and not subject
to PCI data ordering rules.

thanks,
grant