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Part 3: Put period at the end of the sentence

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Hudd 2015-02-01 15:57:11 +00:00
parent 49625488e5
commit 18490a9d67

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@ -265,7 +265,7 @@ We can see the last function call - `go_to_protected_mode` in the [main.c](https
`go_to_protected_mode` defined in the [arch/x86/boot/pm.c](https://github.com/torvalds/linux/blob/master/arch/x86/boot/pm.c#L104). It contains some functions which make last preparations before we can jump into protected mode, so let's look on it and try to understand what they do and how it works.
At first we see call of `realmode_switch_hook` function in the `go_to_protected_mode`. This function invokes real mode switch hook if it is present and disables [NMI](http://en.wikipedia.org/wiki/Non-maskable_interrupt). Hooks are used if bootloader runs in a hostile environment More about hooks you can read in the [boot protocol](https://www.kernel.org/doc/Documentation/x86/boot.txt) (see **ADVANCED BOOT LOADER HOOKS**). `readlmode_swtich` hook presents pointer to the 16-bit real mode far subroutine which disables non-maskable interruptions. After we checked `realmode_switch` hook (it doesn't present for me), there is disabling of non-maskable interruptions:
At first we see call of `realmode_switch_hook` function in the `go_to_protected_mode`. This function invokes real mode switch hook if it is present and disables [NMI](http://en.wikipedia.org/wiki/Non-maskable_interrupt). Hooks are used if bootloader runs in a hostile environment. More about hooks you can read in the [boot protocol](https://www.kernel.org/doc/Documentation/x86/boot.txt) (see **ADVANCED BOOT LOADER HOOKS**). `readlmode_swtich` hook presents pointer to the 16-bit real mode far subroutine which disables non-maskable interruptions. After we checked `realmode_switch` hook (it doesn't present for me), there is disabling of non-maskable interruptions:
```assembly
asm volatile("cli");