VxD and PageNotPresent

[peleon]

Hi,

When I was a little boy, I played with VxD. I remember that I coulndn't access to non present pages from certain parts in Ring-0. Example, when processing interrupt requests.

I guess that your problem might be in accesing those pages from a DEBUG_QUERY event, that as you well have read, it can cause page faults. (dunno about W32_DEVICEIOCONTROL)

It could be a similar mechanism like KMD with PassiveLevel, DispatchLevel....though VxD architecture is quite different from the NT one.

Could you first lock the pages with function like "PageLock", "LinPageLock" and friends?

Hope I'm right, hope it helps

[ajron]

Originally Posted by peleon

I remember that I coulndn't access to non present pages from certain parts in Ring-0. Example, when processing interrupt requests.

I know that processing interrupts is the most restricted area .

I guess that your problem might be in accesing those pages from a DEBUG_QUERY event, that as you well have read, it can cause page faults.

So I move code to other place, but with no positive result ;(.

Could you first lock the pages with function like "PageLock", "LinPageLock" and friends?

I'll try with LinPageLock(), maybe it helps . Thanks.

[ajron]

Yeah, LinPageLock() solves problem . Thanks again.