ECE 391 Lecture 6: Interrupt Handling
Document Summary
2:03 pm x86 isa uses one table for invocation of interrupts, exceptions, system calls called the interrupt descriptor table (idt) This is how you connect physical devices to your system. Summary of the basic characteristics of the summary of three fundamental os services. Asynchronous unexpected examples yes no deliberately via int instruction no. The question: interrupt handlers and programs share resources. What can we do to fix those problems. Obvious things registers solution? save them to the stack memory solution? privatize will still need to share some things; discussed later. Less obvious condition codes solution? again save them to the stack shared data. More subtle external state (e. g. , on devices) compiler optimization (e. g. , volatility) security leaks e. g. , application waits for interrupt, then observes values written by os to stack solution? use separate stack for kernel. If you didn"t have the problem of interrupts.