Page 17 - demo
P. 17

Modes of Operation


















            User Mode                                                         Kernel Mode



            • user program executes in                                        • monitor executes in kernel

                user mode                                                         mode

            • certain areas of memory are                                     • privileged instructions may

                protected from user access                                        be executed

            • certain instructions may not                                    • protected areas of memory
                be executed                                                       may be accessed
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