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Process context switch in the middle of creation/load callback?

henrik_meidahenrik_meida Member Posts: 44

Let's say that i have stored a user-mode address inside of a callback function such as image load callback.

Can a context switch occur in the middle of the function, therefore the user-mode part of the virtual memory changing and therefore my saved user-mode addresses becoming invalid?

If so, what is the best solution to be able to access that user-mode address without any issue?
Is using the MmProbeAndLockPages and putting it inside a try catch the best way to access the saved user-mode address later on in the callback function?

Comments

  • Tim_RobertsTim_Roberts Member - All Emails Posts: 13,970

    An image load callback is called using one of the threads for the process. As long as that thread is in a CPU, that process must remain current. The only way to get in trouble is if you have timers or DPCs, which borrow system threads that are part of another process.

    Tim Roberts, [email protected]
    Providenza & Boekelheide, Inc.

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