Accessing non-existing physical ram.

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YeXo

Accessing non-existing physical ram.

Post by YeXo »

I'm currently writing some code for a memory manager, and I wondered what happens if I map some virtuel memory to non-existing physical memory and I access the virtuel memory. I know I get a page fould if I access non-mapped virtuel memory but what kind of error do I get now?
proxy

Re:Accessing non-existing physical ram.

Post by proxy »

i beleive that writes will be ignored and reads will result in you getting unpredictable data.

proxy
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Candy
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Re:Accessing non-existing physical ram.

Post by Candy »

YeXo wrote: I'm currently writing some code for a memory manager, and I wondered what happens if I map some virtuel memory to non-existing physical memory and I access the virtuel memory. I know I get a page fould if I access non-mapped virtuel memory but what kind of error do I get now?
You don't get an error. You just don't get anything useful either. It could be what you wanted (as if it was memory), it could be a weird trandformation of it, it could be 0, it could be FFFF, it could be your dogs name and in an off-chance it could send your diskdrive in self-destruct mode.
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