Re: MmMapIoSpace for applications in CE 6.0?

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I meant to access a know physical address, of course,
not just physical memory in general. Sorry, it was an
incorrectly asked question.

Steve Maillet (eMVP) wrote:
I think it should be a "back door" somewhere as
is not clear how things like DDRAW will be functioning
if there is no way to access the phys memory from the
user mode directly ...
No one ever said there was no way for user mode code to access physical memory. (Obviously they can or they couldn't even run.) The important distinction here is that the user mode code cannot create mappings of arbitrary physical addresses into user mode space. DDRAW is part of GWES and thus part of the kernel, so it CAN create mappings to a given process on behalf of the user mode code that it's working with. This ensures that the user mode code only has access to what it is supposed to have, and nothing more. This is EXACTLY how the desktop OS versions have worked since the beginning and DDRAW and other technologies like it work perfectly fine there.


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