Hi, I have a doubt about interrupt handling. Can anyone help me ? "How the check for authirized source of an interrupt is done in linux ? If it is done by comparing the CPL with the DPL of IDT or GDT , then if a hardware interrupt comes while the CPU is executing a process in user mode(CPL = 3), so how does the CPU decide whether to handle the interrupt or not ?" Sorry for my poor english. Regards, Roushan -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/