Fix Typos: `parts` --> `part`

mm/linux-mm-1.md

@@ -4,7 +4,7 @@ Linux kernel memory management Part 1.
 Introduction
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-Memory management is one of the most complex (and I think that it is the most complex) parts of the operating system kernel. In the [last preparations before the kernel entry point](http://0xax.gitbooks.io/linux-insides/content/Initialization/linux-initialization-3.html) part we stopped right before call of the `start_kernel` function. This function initializes all the kernel features (including architecture-dependent features) before the kernel runs the first `init` process. You may remember as we built early page tables, identity page tables and fixmap page tables in the boot time. No complicated memory management is working yet. When the `start_kernel` function is called we will see the transition to more complex data structures and techniques for memory management. For a good understanding of the initialization process in the linux kernel we need to have a clear understanding of these techniques. This chapter will provide an overview of the different parts of the linux kernel memory management framework and its API, starting from the `memblock`.
+Memory management is one of the most complex (and I think that it is the most complex) part of the operating system kernel. In the [last preparations before the kernel entry point](http://0xax.gitbooks.io/linux-insides/content/Initialization/linux-initialization-3.html) part we stopped right before call of the `start_kernel` function. This function initializes all the kernel features (including architecture-dependent features) before the kernel runs the first `init` process. You may remember as we built early page tables, identity page tables and fixmap page tables in the boot time. No complicated memory management is working yet. When the `start_kernel` function is called we will see the transition to more complex data structures and techniques for memory management. For a good understanding of the initialization process in the linux kernel we need to have a clear understanding of these techniques. This chapter will provide an overview of the different parts of the linux kernel memory management framework and its API, starting from the `memblock`.
 
 Memblock
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