On Tue, Oct 6, 2009 at 12:33 PM, er krishna <erkrishna@xxxxxxxxx> wrote: > Dear All, > > I have a very basic confusion, please help and confirm the right answer : > > If a process/thread (user space/kernel space) has taken a lock on a > critical section code, and suddenly an interrupt occurs which want to use > the same shared data of critical region. Will it able to preempt this code > which is running in process context ? > > As per my understanding, although interrupts has higher priority than > process, but it can't preempt the process otherwise a major bug can occur ( > depending upon the shared data of critical section). Please confirm my > understanding weather its true or not ? > You are right. If a lock is held, the process cannot be pre-empted by an interrupt which is going to use the same shared data held under lock. The interrupt may be scheduled later or might be lost. -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ