Memory Management Unit: Difference between revisions
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Moved it into the global namespace, going to remove the one in my namespace. Should be a pretty useful article ^_^ |
Categorized to Memory Management |
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And now that we understand how the self-referencing page table trick can be used to read from and write to the current page directory, we'll examine how to read from and write to the page tables in the current process next. A note: 0xFFFFF000 is a valid address to any program unless you map it as SUPERVISOR, or in other words, you leave the USER bit unset. Otherwise programs in userspace will be able to edit their own page tables. Imagine a program deciding to start mapping pages in its address space to the kernel at physical address 0x100000? It could very well now decide to zero out the kernel in RAM.
[[Category:Memory management]]
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