Em Ter, 2009-06-30 às 00:11 +0200, Jiri Slaby escreveu: 
> > pcap_adc_irq actually already runs from a workqueue (pcap_isr_work).
> 
> Aha, thanks, there is a specific irq handler. Ok, sounds fair.
> 
> But interrupts are disabled in pcap_isr_work anyway,

Right.

> so that
> pcap_adc_irq shouldn't sleep, right? Or maybe I missed something again...

No. Interrupts are enabled again before pcap_adc_irq() runs.

pcap_isr_work() doesn't call pcap_adc_irq directly, it calls the
irq_flow_handler, handle_simple_irq(), which needs to run with
interrupts disabled. Interrupts are enabled again on handle_IRQ_event(),
as pcap_adc_irq is requested _without_ IRQF_DISABLED.

-- 
Daniel Ribeiro