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SubjectInterrupts
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Hi there,

I am trying to understand the interrupts mechanism in the kernel. Please
correct me if I am wrong.

All interrupts go thru the do_irq function and this function
acknowledges the interrupt to the PIC (by sending to port 0x20 or 0xa0)
before handling it.

I was just wondering why this is done before handling the interrupt. In
other code I have seen this done after the interrupt is handled (they
called it an "EOI" (end of interrupt)).

How does this mechanism work when multiple devices share one IRQ?


Thanks,
Seth

PS: Please respond via e-mail because I am in the process of trying to
re-subscribe. Apparently, vger replies to one of my majordomo queries
once per 2 days :)




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