Date: Mon, 30 Nov 2009 22:59:43 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
cc: Russell King - ARM Linux <linux@arm.linux.org.uk>,
       =?ISO-8859-15?Q?Uwe_Kleine-K=F6nig?= 
	<u.kleine-koenig@pengutronix.de>,
       Rusty Russell <rusty@rustcorp.com.au>,
       David Brownell <dbrownell@users.sourceforge.net>,
       Eric Miao <eric.y.miao@gmail.com>,
       Peter Zijlstra <a.p.zijlstra@chello.nl>,
       John Stultz <johnstul@us.ibm.com>, Nicolas Pitre <nico@marvell.com>,
       Jamie Lokier <jamie@shareable.org>, LKML <linux-kernel@vger.kernel.org>,
       Remy Bohmer <linux@bohmer.net>,
       Hugh Dickins <hugh.dickins@tiscali.co.uk>,
       linux-arm-kernel@lists.infradead.org,
       Andrea Gallo <andrea.gallo@stericsson.com>,
       Andrew Morton <akpm@linux-foundation.org>,
       Linus Torvalds <torvalds@linux-foundation.org>,
       Ingo Molnar <mingo@elte.hu>
Subject: Re: Get rid of IRQF_DISABLED - (was [PATCH] genirq: warn about
 IRQF_SHARED|IRQF_DISABLED)
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On Mon, 30 Nov 2009, Alan Cox wrote:

> > However, I think we still have a number of corner cases.  The SMC91x
> > driver comes to mind, with its stupidly small FIFOs, where the majority
> > of implementations have to have the packets loaded via PIO - and this
> > seems to generally happen from IRQ context.
> 
> Everything 8390 based is in the same boat. It relies on being able to
> use disable_irq_nosync/enable_irq and knows all about the joys of
> interrupt bus asynchronicity internally. That does however allow it to
> get sane results by using the irq controller to mask the potentially
> shared IRQ at source.

So that would be a known candidate for IRQF_NEEDS_IRQS_ENABLED, right?

Either that or we decide to push such beasts into the threaded irq
space to keep them working until the last card hits the trashcan. I
know that this would still need to disable the interrupt on the PIC
level, but we have already mechanisms for that in the threaded code.

Thanks,

	tglx


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