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Fixes bad URL from post-09 address calculation section (#1146)

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2022-10-03 03:32:07 -07:00
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blog/content/edition-2/posts/09-paging-implementation/index.md
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@@ -147,7 +147,7 @@ In the section below, we explain how to construct virtual addresses for followin
We saw that we can access tables of all levels by following the recursive entry once or multiple times before the actual translation. Since the indexes into the tables of the four levels are derived directly from the virtual address, we need to construct special virtual addresses for this technique. Remember, the page table indexes are derived from the address in the following way:
![Bits 0–12 are the page offset, bits 12–21 the level 1 index, bits 21–30 the level 2 index, bits 30–39 the level 3 index, and bits 39–48 the level 4 index](../08-paging-introduction/x86_64-table-indices-from-address.svg)
![Bits 0–12 are the page offset, bits 12–21 the level 1 index, bits 21–30 the level 2 index, bits 30–39 the level 3 index, and bits 39–48 the level 4 index](../paging-introduction/x86_64-table-indices-from-address.svg)
Let's assume that we want to access the level 1 page table that maps a specific page. As we learned above, this means that we have to follow the recursive entry once before continuing with the level 4, level 3, and level 2 indexes. To do that, we move each block of the address one block to the right and set the original level 4 index to the index of the recursive entry: