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STATUS_INVALID_ADDRESS
STATUS_INVALID_ADDRESS (0xC0000141) is a generic error code that can be returned by many kernel functions and is also generated by user drivers. The name conveys the essence of the problem - the address is not correct. What address is meant depends on the driver or function that produces that error code. For example, MmMapLockedPagesSpecifyCache may return this error if the RequestedAddress parameter is incorrect.
Kernel mode
Windows NT kernel mode has full access to the hardware and system resources of the computer and runs code in a protected memory area. It controls access to scheduling, thread prioritization, memory management and the interaction with hardware. The kernel mode stops user mode services and applications from accessing critical areas of the operating system that they should not have access to; user mode processes must ask the kernel mode to perform such operations on their behalf.
While the x86 architecture supports four different privilege levels (numbered 0 to 3), only the two extreme privilege levels are used. Usermode programs are run with CPL 3, and the kernel runs with CPL 0. These two levels are often referred to as "ring 3" and "ring 0", respectively. Such a design decision had been done to achieve code portability to RISC platforms that only support two privilege levels,[9] though this breaks compatibility with OS/2 applications that contain I/O privilege segments that attempt to directly access hardware.
Code running in kernel mode includes: the executive, which is itself made up of many modules that do specific tasks; the kernel, which provides low-level services used by the Executive; the Hardware Abstraction Layer (HAL); and kernel drivers.
Memory Manager
Manages virtual memory, controlling memory protection and the paging of memory in and out of physical memory to secondary storage, and implements a general-purpose allocator of physical memory. It also implements a parser of PE executables that lets an executable be mapped or unmapped in a single, atomic step.
Starting from Windows NT Server 4.0, Terminal Server Edition, the memory manager implements a so-called session space, a range of kernel-mode memory that is subject to context switching just like user-mode memory. This lets multiple instances of the kernel-mode Win32 subsystem and GDI drivers run side-by-side, despite shortcomings in their initial design. Each session space is shared by several processes, collectively referred to as a "session".
To ensure a degree of isolation between sessions without introducing a new object type, the association between processes and sessions is handled by the Security Reference Monitor, as an attribute of a security subject (token), and it can only be changed while holding special privileges.
The relatively unsophisticated and ad hoc nature of sessions is due to the fact they weren't part of the initial design, and had to be developed, with minimal disruption to the main line, by a third party (Citrix Systems) as a prerequisite for their terminal server product for Windows NT, called WinFrame. Starting with Windows Vista, though, sessions finally became a proper aspect of the Windows architecture. No longer a memory manager construct that creeps into user mode indirectly through Win32, they were expanded into a pervasive abstraction affecting most Executive subsystems. As a matter of fact, regular use of Windows Vista always results in a multi-session environment.