I want to obtain the beginning of a memory page, a page that contains a function. In my case I try to achieve the page beginning of main function. Which lies in 0x400a80, I think it is in code section of memory. I would appreciate if you can verify whether it is true or not. As far as I understood, adress 0x400a80 lies in a page. When I show memory segments of my process with pmap, it shows a segment starting with 0x400000 with size 8K, and the next portion goes with 0x601000 with size 4K. I want to obtain adress 0x400000 because it has the address of the main() function. How can I achieve starting adress of a page when I have an adress that resides in that page? Is there any built-in way to do in linux ?

I have some questions on the Kernel mapping of a Linux process' higher virtual address: 1. Is that maps to the kernel text segment which is stored in the RAM(I read the

will be extracted to the RAM)? 2. What is the use of it? 3. The pmap of a process shows it's mapping to the exe's segments, shared memory,stack,heap. Can I see the higher address kernel mapped also?

Does the Linux command "pmap" always give the total memory usage in kilobytes?

$ pmap 3208920 | tail -n 1 
 total            71836K

I would like to get a process's memory usage and it seems that pmap can do that. However, the value it returns is different from what I see in top command. # pmap 22080 | grep total total 6588952K # top | grep 22080 22080 ghatee 20 0 6588948 5.873g 11936 R 100.0 9.4 1120:17 pw.x What is the reason?

I use pmap for inspecting the memory map of the user-space process ``. How to inspect the memory map of the kernel given "root" privileges (i.e. all capabilities)? The reason I'm interested is that I'm developing kernel modules, and thus would like to know which memory segment/section a symbol resides in. **Bonus**: Also, in order to obtain this information "offline", I've tried as follows: $ sudo readelf -a /boot/vmlinuz-5.8.0-50-generic readelf: Error: Not an ELF file - it has the wrong magic bytes at the start But apparently, the Linux image is not in ELF format (why?). How can I see the segments/sections of the kernel image?

I know that

of a process shows how the memory mapping is done. For example, the first lines of pmap output shows the memory mapping to the text segment of the process' executable. Assume I have a really big executable and my code size is large. For a small text segment(small executable) the pmamp shows

- 401000 - 4096 B    - 4 KiB

of text segment mapped. (1) If the text segment is really large how does it map? (2) Is it map dynamically based on the pages required as part of the code execution progress?

I want to get the memory consumption by a process. I am using *RSS* parameter to determine it. I am getting same *RSS* value when I am using pmap -xx and with smem tool. But when I am using ps v to get the RSS then it is showing different value. I know for pmap and smem they use /proc/pid/smaps file to get *RSS* value but I don't have idea about ps tool. What are the basis of this calculation in ps tool and which is correct ps or pmap and smem