Virtual Address Space

[Alexander Kapshuk]

On Wed, Sep 28, 2016 at 8:06 AM, Madhu K <madhu.sk89 at gmail.com> wrote:
> Hi All,
>
> This is to understand the Virtual address space.Basically who generates the
> virtual addresses CPU or GNU compiler?
>
> Thanks
> Madhu
>
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In no way does this response claim to be based on personal expert
knowledge, but if my understanding of Chapter 2 (Page tables) of
https://pdos.csail.mit.edu/6.828/2016/xv6/book-rev9.pdf is correct, it
is the hardware that performs the mapping of physical memory, RAM, to
virtual addresses on x86:
Quote:
As a reminder, x86 instructions (both user and kernel) manipulate
virtual addresses. The machine’s RAM, or physical memory, is indexed
with physical addresses. The x86 page table hardware connects these
two kinds of addresses, by mapping each virtual address to a physical
address.