THREAD_NOT_MUTEX_OWNER
Mutex ownership violation
THREAD_NOT_MUTEX_OWNER is bug check code 0x00000011. Kernel mutexes are thread-owned synchronization objects. This bug check indicates that ownership bookkeeping no longer matches the release or wait path, usually because a driver used the wrong object, wrong thread context, or bad unwind path.
How to read it in a dump
- Identify the thread in the dump and compare it with the mutex owner.
- Look for APC, worker-thread, completion, or cleanup paths that run in a different thread than the acquisition path.
- This is separate from spin-lock misuse because mutex ownership is tied to a thread.
What to check
- Verify that lock release occurs in the same ownership model used for acquisition.
- Inspect handoff between system threads, work items, callbacks, and cancel routines.
- Use verifier deadlock detection for repeatable ownership and ordering failures.
References
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