interrupt

I have an Arduino Uno (awesome little device!). It has two interrupts; let's call them 0 and 1 . I attach a handler to interrupt 0 and a different one to interrupt 1, using attachInterrupt() : http://www.arduino.cc/en/Reference/AttachInterrupt . Interrupt 0 is triggered and it calls its handler, which does some number crunching. If interrupt 0 's handler is still executing when interrupt 1 is triggered, what will happen? Will interrupt 1 interrupt interrupt 0 , or will interrupt 1 wait until interrupt 0 's handler is done executing? Please note that this question specifically relates to

All is in the title. Any links to good documentations are welcome. The local timer interrupt is a timer implemented on the APIC that interrupts only a particular CPU instead of raising an interrupt that can be handled by any CPU. It's discussed in Bovet & Cesati's "Understanding the Linux Kernel". A snippet: The local APIC present in recent 80x86 microprocessors (see the section “Interrupts and Exceptions” in Chapter 4) provides yet another time-measuring device: the CPU local timer. The CPU local timer is a device similar to the Programmable Interval Timer just described that can issue one

When you disable interrupts (with the cli instruction in x86), what exactly happens? Does the PIC wait for you to turn on interrupts, and fire the interrupt when that happens? (If so, how long does it wait, and what happens if the time 'expires'?) Does the interrupt -- from the device's perspective -- get sent into a "black hole", with no response? Does the PIC somehow tell the device that "the CPU is busy" or something? Or does something else happen? Also, how do you deal with an interrupt you don't know how to handle? Is there some way to tell the PIC (or the device, if you don't know what

I am writing a simple kernel module, which could register an interrupt and handle it. However, when I try to register interrupt by calling the request_irq function, it returns error code -22 : ERROR: Cannot request IRQ 30 - code -22 , EIO 5 , EINVAL 22 I believe, this error code is equal to EINVAL (invalid argument) Please tell me, what I am doing wrong. Here is a module: #include <linux/init.h> #include <linux/module.h> #include <linux/irq.h> #include <linux/io.h> #include <linux/irqdomain.h> #include <linux/interrupt.h> #include <linux/of.h> #include <linux/of_address.h> #include <asm