Messages in this thread | | | Subject | Re: lockdep and threaded IRQs (was: ...) | From | Peter Zijlstra <> | Date | Tue, 03 Mar 2009 10:27:26 +0100 |
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On Mon, 2009-03-02 at 18:37 -0800, David Brownell wrote: > No. But I did get a non-response that didn't include any > explanation, and relied totally on unfounded assertions > combined with the presumption that someday IRQF_DISABLED > will be forced on in all drivers.
Enabling IRQs in hardirq context is BAD because:
- IRQ handler nesting leads to stack overflow - It gives the false impression its OK for IRQ handlers to be slow, it is _NOT_, as you still generate horrible preemption latency.
Therefore IRQF_DISABLED _will_ be forced on everybody some day soon, and I'll provide an IRQF_ENABLED for use by broken hardware only (and make a TAINT flag for that too).
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