pkspin_lock PKSPIN_LOCK - android-download-iso PKSPIN_LOCK Understanding the PKSPIN_LOCK in Windows Kernel Development

3-patti-super-apk The PKSPIN_LOCK, a fundamental construct in Windows kernel-mode programming, plays a crucial role in ensuring data integrity and preventing race conditions in multithreaded environmentsntoskrnl/ke/amd64/spinlock.c File Reference This article delves into the intricacies of the PKSPIN_LOCK, exploring its purpose, how it's utilized, and its significance within the Windows operating system, particularly as seen in the ntoskrnlPKSPIN_LOCKloc FIXME("(%p %p) stub\n", head, lock); return NULL; } + + PKSPIN_LOCKlock) +#else +PLIST_ENTRY WINAPI ExfInterlockedRemoveHeadList exe and Windows drivers documentationntoskrnl/ke/amd64/spinlock.c File Reference

What is a PKSPIN_LOCK?

A PKSPIN_LOCK is a synchronization primitive that operates as a highly optimized, short-term lockPKSPIN_LOCK· PKTMOBJECT_CURSOR · PKTMOBJECT_TYPE · PLARGE_INTEGER · PLASTINPUTINFO · PLAYERPLANEDESCRIPTOR · PLCID · PLDT_ENTRY · PLIST_ENTRY · PLIST_ENTRY32  Its primary function is to protect shared resources from being accessed concurrently by multiple threads or processorsPKSPIN_LOCK· PKTMOBJECT_CURSOR · PKTMOBJECT_TYPE · PLARGE_INTEGER · PLASTINPUTINFO · PLAYERPLANEDESCRIPTOR · PLCID · PLDT_ENTRY · PLIST_ENTRY · PLIST_ENTRY32  When a thread needs to access a shared resource, it first attempts to acquire the PKSPIN_LOCKKfReleaseSpinLock - Windows drivers If the lock is available, the thread acquires it and proceeds with its operation201454—FORCEINLINE · VOID · NTAPI · KeInitializeSpinLock ( · __outPKSPIN_LOCKSpinLock · ) · { · *SpinLock = 0;. If the lock is already held by another thread, the requesting thread will spin (repeatedly check) until the lock is releasedPKSPIN_LOCK· PKTMOBJECT_CURSOR · PKTMOBJECT_TYPE · PLARGE_INTEGER · PLASTINPUTINFO · PLAYERPLANEDESCRIPTOR · PLCID · PLDT_ENTRY · PLIST_ENTRY · PLIST_ENTRY32  This spinning mechanism is why it's termed a "spin lock202149— ((PKSPIN_LOCK)(v8 + 20304)); for ( i = *(__int64 **)(a2 + 112); i; i = (__int64 *)*i ) NetioExpandNetBuffer(v15, i + 2, *((unsigned int *)i + "

The structure of a PKSPIN_LOCK is typically a simple data type, often a `ULONG` or `KSPIN_LOCK` pointer, as indicated by various function signatures like `KeInitializeSpinLock ( __outPKSPIN_LOCK SpinLock )`494Kii386SpinOnSpinLock(PKSPIN_LOCKSpinLock, ULONG Flags). 495{. 496 // FIXME Handle flags. 497 UNREFERENCED_PARAMETER(Flags);. 498. 499 /* Spin until it's  The initialization of a spin lock is a critical step, often performed using functions like `KeInitializeSpinLock` to set the lock to an available state, ready for acquisitionPKSPIN_LOCKSpinLock ) /*++ Routine Description This function acquires a queued spin lock at the current IRQL. Arguments LockQueue - Supplies a pointer to 

Acquiring and Releasing the PKSPIN_LOCK

The core operations involving a PKSPIN_LOCK are acquiring and releasing itCVE-2021-24074 TCP/IP协议栈漏洞分析 In the Windows kernel, these actions are managed by specific functions:

* Acquisition: Functions like `KeAcquireSpinLock`, `KfAcquireSpinLock`, and `KeAcquireInStackQueuedSpinLock` are used to obtain the lock198967—ExInterlockedAddUshort (. IN PUSHORT Addend,. IN USHORT Increment,. INPKSPIN_LOCKLock. Copyright (c) Microsoft Corporation - Use subject to  These functions not only acquire the lock but may also manipulate the IRQL (Interrupt Request Level)KeAcquireInStackQueuedSpinLo For example, `KeAcquireSpinLockRaiseToDpc` suggests that acquiring the lock might raise the IRQL to `DISPATCH_LEVEL`, a common practice in kernel operations to prevent interruptions that could lead to deadlockswinddk.h The `KSPIN_LOCK` parameter is a pointer to the spin lock itself, and the `KIRQL` parameter, often returned upon acquisition, signifies the IRQL level before the lock was taken202149— ((PKSPIN_LOCK)(v8 + 20304)); for ( i = *(__int64 **)(a2 + 112); i; i = (__int64 *)*i ) NetioExpandNetBuffer(v15, i + 2, *((unsigned int *)i + 

* Release: Correspondingly, functions such as `KeReleaseSpinLock` and `KfReleaseSpinLock` are used to release the lock2025523—Syntax. C++. Copy. KIRQL KfAcquireSpinLock(PKSPIN_LOCKSpinLock );. Parameters. SpinLock. Pointer to an initialized KSPIN_LOCK spin lock for  When releasing, the `KIRQL NewIrql` parameter is often provided to restore the IRQL to its previous state, ensuring proper system operation2025523—Syntax. C++. Copy. KIRQL KfAcquireSpinLock(PKSPIN_LOCKSpinLock );. Parameters. SpinLock. Pointer to an initialized KSPIN_LOCK spin lock for 

The concept of queued spin locks, as seen with `KeAcquireInStackQueuedSpinLock` and `queuelockOF_SHARE_DENY_NONE in win32api_rs_sys - Rustc`, introduces an additional layer of managementPKSPIN_LOCK· PKTMOBJECT_CURSOR · PKTMOBJECT_TYPE · PLARGE_INTEGER · PLASTINPUTINFO · PLAYERPLANEDESCRIPTOR · PLCID · PLDT_ENTRY · PLIST_ENTRY · PLIST_ENTRY32  These may provide fairer acquisition by queuing waiting threads in a first-in, first-out manner, reducing contention and improving efficiency in high-throughput scenariosKfAcquireSpinLock - Windows drivers

Why are PKSPIN_LOCKs Necessary?

In a preemptive multitasking operating system like Windows, multiple threads can execute concurrently on different processors or be interleaved on a single processorWindows Ancillary Function Driver (afd.sys) Race- When these threads need to access or modify shared data structures—such as buffers, lists, or control blocks—without proper synchronization, race conditions can occurPKSPIN_LOCK· PKTMOBJECT_CURSOR · PKTMOBJECT_TYPE · PLARGE_INTEGER · PLASTINPUTINFO · PLAYERPLANEDESCRIPTOR · PLCID · PLDT_ENTRY · PLIST_ENTRY · PLIST_ENTRY32  A race condition happens when the outcome of an operation depends on the unpredictable timing of events201454—FORCEINLINE · VOID · NTAPI · KeInitializeSpinLock ( · __outPKSPIN_LOCKSpinLock · ) · { · *SpinLock = 0;.

For instance, if two threads attempt to add an item to the same linked list simultaneously, and both read the current tail pointer before either updates it, one of the additions might be lost, leading to data corruptionIoConnectInterruptEx- MessageBased - API issues The PKSPIN_LOCK prevents this by ensuring that only one thread can modify the shared data structure at any given momentKfAcquireSpinLock - Windows drivers

The necessity of PKSPIN_LOCK is evident in various kernel components, including interrupt handling routines (indicated by `KIRQL`), driver development, and interlocked operationsKfReleaseSpinLock - Windows drivers Functions like `ExInterlockedAddUshort` demonstrate how spin locks are integrated with other interlocked operations to maintain atomicityntoskrnl/ke/amd64/spinlock.c File Reference

Verifiable Information and Parameters

The functions interacting with PKSPIN_LOCK typically involve the following parameters:

* `PKSPIN_LOCK SpinLock`: A pointer to the KSPIN_LOCK structure or variable that represents the spin lockPKSPIN_LOCK· PKTMOBJECT_CURSOR · PKTMOBJECT_TYPE · PLARGE_INTEGER · PLASTINPUTINFO · PLAYERPLANEDESCRIPTOR · PLCID · PLDT_ENTRY · PLIST_ENTRY · PLIST_ENTRY32  This is the core entity being managed18.driverbase-自旋锁（SpinLock）wrk代码分析原创

* `KIRQL OldIrql` / `KIRQL NewIrql`: Represents the Interrupt Request Levelntoskrnl/ke/spinlock.c Source File These are crucial for managing the system's responsiveness during critical sections protected by the spin lockKfAcquireSpinLock - Windows drivers The IRQL is often raised to `DISPATCH_LEVEL` or higher to prevent interruptions from interfering with lock-protected code20081012—INPKSPIN_LOCKSpinLock, OUT PKIRQL OldIrql ); VOID KeReleaseSpinLock( INPKSPIN_LOCKSpinLock, IN KIRQL NewIrql ); 获取时做了哪些工作呢 

* `PKLOCK_QUEUE_HANDLE LockHandle`: Used in conjunction with queued spin locks to manage the queue of waiting threads18.driverbase-自旋锁（SpinLock）wrk代码分析原创

The source code snippets from `ntoskrnl/ke/amd64/spinlock2025612— KeAcquireInStackQueuedSpinLock((PKSPIN_LOCK)v13, &LockHandle); v24 = 1; CqSize = v14->CqSize; v31 = CqSize; MappedMemory = (unsigned int *) c` and `wdk\u4e2d\u4f7f\u7528\u81ea\u65cb\u9501SpinLock\u7684\u539f\u5219\u53ca\u539f\u56e0\u5206\u6790\u539f\u521b` provide concrete examples of how these functions are defined and used within the kernelKfAcquireSpinLock - Windows drivers For instance, `KeAcquireSpinLockRaiseToDpc (PKSPIN_LOCK SpinLock)` is a direct illustration of acquiring a spin lock and raising the IRQLspinlock.asm

Related Concepts and Variations

While PKSPIN_LOCK is the primary term, the related search terms highlight variations and associated concepts:

* Queued Spin Locks: As mentioned, these offer a more structured approach to managing contention201454—FORCEINLINE · VOID · NTAPI · KeInitializeSpinLock ( · __outPKSPIN_LOCKSpinLock · ) · { · *SpinLock = 0;.

* Interlocked Operations: Functions like `ExInterlockedAddUshort` often use PKSPIN_LOCK internally or in conjunction with their operations to ensure atomicityPKSPIN_LOCK· PKTMOBJECT_CURSOR · PKTMOBJECT_TYPE · PLARGE_INTEGER · PLASTINPUTINFO · PLAYERPLANEDESCRIPTOR · PLCID · PLDT_ENTRY · PLIST_ENTRY · PLIST_ENTRY32 

* IRQL Management: The close relationship between spin lock usage and IRQL manipulation is a recurring theme, underscoring the importance of understanding kernel synchronization at different interrupt levels494Kii386SpinOnSpinLock(PKSPIN_LOCKSpinLock, ULONG Flags). 495{. 496 // FIXME Handle flags. 497 UNREFERENCED_PARAMETER(Flags);. 498. 499 /* Spin until it's 

* `winddkqueuelock.ch` and `ks20081012—INPKSPIN_LOCKSpinLock, OUT PKIRQL OldIrql ); VOID KeReleaseSpinLock( INPKSPIN_LOCKSpinLock, IN KIRQL NewIrql ); 获取时做了哪些工作呢 h`: These header files are crucial as they define the `KSPIN_LOCK` type and related synchronization structures and functions used by driver developersPKSPIN_LOCK; typedef ULONG KAFFINITY, *PKAFFINITY; typedef CCHAR KPROCESSOR_MODE; typedef enum _MODE { KernelMode, UserMode, MaximumMode } MODE 

Conclusion

The PKSPIN_LOCK is an indispensable component of the Windows kernel, providing essential data protection mechanisms in a concurrent execution environmentKeAcquireInStackQueuedSpinLo By understanding its acquisition, release, and the underlying principles of interrupt level management, developers can effectively build robust and reliable kernel-mode drivers and applications2025523—Syntax. C++. Copy. KIRQL KfAcquireSpinLock(PKSPIN_LOCKSpinLock );. Parameters. SpinLock. Pointer to an initialized KSPIN_LOCK spin lock for  The consistent documentation of PKSPIN_LOCK across various Windows driver resources and kernel source files reinforces its critical role in maintaining system stability and performancespinlock.asm