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I have a client who has asked me to chase down some APC_INDEX_MISMATCH crashes. The crash says some driver has disabled kernel APCs without re-enabling them. The suspect driver is a registry callback filter, but it does nothing that would affect the APC state. The BSOD happens in their Windows service, but not inside their driver. Their driver IS running in another CPU, but it has just started a callback and is still fetching handles and contexts.
So, what seemingly innocent operations would disable kernel APCs? Are these mismatches detected immediately, or can this be leftover from other operations? I'm suspicious because the thread being blamed is not the one with the suspect driver, although it's doing an inverted call completion for every filtered operation, so the service interacts with the driver a lot.
Tim Roberts, [email protected]
Providenza & Boekelheide, Inc.
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