Re: Understanding the mapping of physical memory to kernel address space

2015-03-15 Thread Sunny Shah
Hi Arun, Thanks for that excellent explanation. It's more or less clear to me now. However, quoting what you said: Because we have plenty of kernel virtual address(3GB) and can easily map 2GB of RAM in to it. Why should we have to map the whole RAM into the KVA? Shouldn't it be only LOW_MEM?

Re: Understanding the mapping of physical memory to kernel address space

2015-03-15 Thread Arun KS
On Mar 15, 2015 8:27 PM, Sunny Shah shahsunny...@gmail.com wrote: Hi Arun, Thanks for that excellent explanation. It's more or less clear to me now. However, quoting what you said: Because we have plenty of kernel virtual address(3GB) and can easily map 2GB of RAM in to it. Why should

Re: Understanding the mapping of physical memory to kernel address space

2015-03-15 Thread Sunny Shah
Thank you so much !! On Sun, Mar 15, 2015 at 8:48 PM, Arun KS getaru...@gmail.com wrote: On Mar 15, 2015 8:27 PM, Sunny Shah shahsunny...@gmail.com wrote: Hi Arun, Thanks for that excellent explanation. It's more or less clear to me now. However, quoting what you said: Because

Re: Understanding the mapping of physical memory to kernel address space

2015-03-15 Thread Arun KS
Hello Sunny, On Sat, Mar 14, 2015 at 8:25 PM, Sunny Shah shahsunny...@gmail.com wrote: Thank you guys! I have two more questions from your replies: I thought I had understood HIGH_MEM and LOW_MEM, but it appears I was wrong. Does the concept of high memory/low memory correspond to physical

Re: Understanding the mapping of physical memory to kernel address space

2015-03-14 Thread Sunny Shah
Thank you guys! I have two more questions from your replies: - I thought I had understood HIGH_MEM and LOW_MEM, but it appears I was wrong. Does the concept of high memory/low memory correspond to physical address space or virtual address space? Also, does LOW_MEM always have to be 1

Understanding the mapping of physical memory to kernel address space

2015-03-12 Thread Sunny Shah
Hello, This is my first mail on this list, so please let me know if I'm erring. I'm reading Bovet and Cesati's Understanding the Linux Kernel, specifically the chapter Memory Addressing, sub-section Kernel Page Tables. Here they describe how Linux initializes its page tables for various RAM

RE: Understanding the mapping of physical memory to kernel address space

2015-03-12 Thread Jeff Haran
-Original Message- From: kernelnewbies-boun...@kernelnewbies.org [mailto:kernelnewbies-boun...@kernelnewbies.org] On Behalf Of Arun KS Sent: Thursday, March 12, 2015 11:03 AM To: Sunny Shah Cc: kernelnewbies Subject: Re: Understanding the mapping of physical memory to kernel address

Re: Understanding the mapping of physical memory to kernel address space

2015-03-12 Thread Arshad Hussain
On 12-Mar-2015, at 10:02 am, Sunny Shah shahsunny...@gmail.com wrote: Hello, This is my first mail on this list, so please let me know if I'm erring. I'm reading Bovet and Cesati's Understanding the Linux Kernel, specifically the chapter Memory Addressing, sub-section Kernel Page

Re: Understanding the mapping of physical memory to kernel address space

2015-03-12 Thread Arun KS
Hello Sunny, On Thu, Mar 12, 2015 at 10:32 PM, Sunny Shah shahsunny...@gmail.com wrote: Hello, This is my first mail on this list, so please let me know if I'm erring. I'm reading Bovet and Cesati's Understanding the Linux Kernel, specifically the chapter Memory Addressing, sub-section