Hello everyone, I would like to understand something about the pagefault mechanism (focusing on userspace memory) in the kernel. First, is the lazy allocation of memory at userspace. Right? So theoretically no memory is actually allocated, till it is actually used at writeout. Once written out at userspace level, a pagefault will occur, and then actual memory allocated (or perhaps old memory contents swapped back from swapfile). And this memory is always allocated in the HIGHMEM zone, correct? The entire processing have different parts that is interrupt-disabled and interrupt-enabled. But what about CPU? While the userspace application is waiting for the stuff to be copied to memory, the whole process will block, and then kernel pagefault mechanism takes place.....different CPU may be involved, right? So long as interrupt is enabled, CPU transition can happened, correct? Feel free to correct any or all parts of my statements - just mentioned it without much checking. Thank you for the sharing. -- Regards, Peter Teoh -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ