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Subject: Re: [PATCH] Prevent nested interrupts when the IRQ stack is near
 overflowing v2
From: Peter Zijlstra <peterz@infradead.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
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Date: Thu, 25 Mar 2010 19:21:22 +0100
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On Thu, 2010-03-25 at 11:01 -0700, Linus Torvalds wrote:
> Are there any cases around 
> that still have busy-loop delays based on real-time in their irq handlers? 
> I simply don't know. 

I recently found a few in drivers/net/ there's all kinds of funny stuff
in there.. not sure how common the matching hardware is though.

One thing we could do is instrument jiffies to yell when its used from
hardirq context and fix up these things.

But yeah, there's funky hardware around, but I think we should provide
more incentives to keep modern hardware drivers saner.