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Fix broken links in “Double Faults” (#275)

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Philipp Oppermann
2017-01-02 19:39:19 +01:00
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parent 1549e318a5
commit f6a1faab96
1 changed files with 3 additions and 3 deletions
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blog/post/12-double-faults.md
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@@ -366,8 +366,8 @@ impl MemoryController {
``` ```
The `MemoryController` struct holds the three types that are required for `alloc_stack` and provides a simpler interface (only one argument). The `alloc_stack` wrapper just takes the tree types as `&mut` through [destructuring] and forwards them to the `stack_allocator`. The [ref mut]-s are needed to take the inner fields by mutable reference. Note that we're re-exporting the `Stack` type since it is returned by `alloc_stack`. The `MemoryController` struct holds the three types that are required for `alloc_stack` and provides a simpler interface (only one argument). The `alloc_stack` wrapper just takes the tree types as `&mut` through [destructuring] and forwards them to the `stack_allocator`. The [ref mut]-s are needed to take the inner fields by mutable reference. Note that we're re-exporting the `Stack` type since it is returned by `alloc_stack`.
[destructuring]: http://rust-lang.github.io/book/chXX-patterns.html#Destructuring [destructuring]: http://rust-lang.github.io/book/ch18-00-patterns.html#Destructuring
[ref mut]: http://rust-lang.github.io/book/chXX-patterns.html#ref-and-ref-mut [ref mut]: http://rust-lang.github.io/book/ch18-00-patterns.html#ref-and-ref-mut
The last step is to create a `StackAllocator` and return a `MemoryController` from `memory::init`: The last step is to create a `StackAllocator` and return a `MemoryController` from `memory::init`:
@@ -500,7 +500,7 @@ pub fn init(memory_controller: &mut MemoryController) {
We define that the 0th IST entry is the double fault stack (any other IST index would work too). We create a new TSS through the `TaskStateSegment::new` function and load the top address (stacks grow downwards) of the double fault stack into the 0th entry. We define that the 0th IST entry is the double fault stack (any other IST index would work too). We create a new TSS through the `TaskStateSegment::new` function and load the top address (stacks grow downwards) of the double fault stack into the 0th entry.
#### Loading the TSS #### Loading the TSS
Now that we created a new TSS, we need a way to tell the CPU that it should use it. Unfortunately, this is a bit cumbersome, since the TSS is a Task State _Segment_ (for historical reasons). So instead of loading the table directly, we need to add a new segment descriptor to the [Global Descriptor Table] (GDT). Then we can load our TSS invoking the [`ltr` instruction] with the respective GDT index. Now that we created a new TSS, we need a way to tell the CPU that it should use it. Unfortunately, this is a bit cumbersome, since the TSS is a Task State _Segment_ (for historical reasons). So instead of loading the table directly, we need to add a new segment descriptor to the [Global Descriptor Table] \(GDT). Then we can load our TSS invoking the [`ltr` instruction] with the respective GDT index.
[Global Descriptor Table]: http://www.flingos.co.uk/docs/reference/Global-Descriptor-Table/ [Global Descriptor Table]: http://www.flingos.co.uk/docs/reference/Global-Descriptor-Table/
[`ltr` instruction]: http://x86.renejeschke.de/html/file_module_x86_id_163.html [`ltr` instruction]: http://x86.renejeschke.de/html/file_module_x86_id_163.html