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Move old exception posts to old_posts folder

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Philipp Oppermann
2017-03-25 16:39:33 +01:00
parent 839cf7fba4
commit 3e5eceb1b3
5 changed files with 4 additions and 4 deletions
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blog/content/post/02-entering-longmode.md
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@@ -499,8 +499,8 @@ _Congratulations_! You have successfully wrestled through this CPU configuration
#### One Last Thing
Above, we reloaded the code segment register `cs` with the new GDT offset. However, the data segment registers `ss`, `ds`, `es`, `fs`, and `gs` still contain the data segment offsets of the old GDT. This isn't necessarily bad, since they're ignored by almost all instructions in 64-bit mode. However, there are a few instructions that expect a valid data segment descriptor _or the null descriptor_ in those registers. An example is the the [iretq] instruction that we'll need in the [_Returning from Exceptions_] post.
[iretq]: {{% relref "11-returning-from-exceptions.md#the-iretq-instruction" %}}
[_Returning from Exceptions_]: {{% relref "11-returning-from-exceptions.md" %}}
[iretq]: {{% relref "returning-from-exceptions.md#the-iretq-instruction" %}}
[_Returning from Exceptions_]: {{% relref "returning-from-exceptions.md" %}}
To avoid future problems, we reload all data segment registers with null: