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Date: Tue, 02 Feb 2010 14:23:08 -0700
From: Dan Williams <dan.j.williams@intel.com>
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To: "Ira W. Snyder" <iws@ovro.caltech.edu>
Subject: Re: [PATCH 8/8] fsldma: major cleanups and fixes
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Ira W. Snyder wrote:
> In the fsldma driver, all callbacks are run from tasklet (softirq)
> context. That's under local_irq_disable(), right? Hardirq's certainly
> aren't disabled there.

Actually, my mistake, the cleanup routine does spin_lock_irqsave(), but 
I now see that it drops the lock across the callback:

/* Run the link descriptor callback function */
if (callback) {
	spin_unlock_irqrestore(&fsl_chan->desc_lock, flags);
	dev_dbg(fsl_chan->dev, "link descriptor %p callback\n", desc);
	callback(callback_param);
	spin_lock_irqsave(&fsl_chan->desc_lock, flags);
}

...so I retract my comment about surprising the raid5 code.

--
Dan