help needed to do mmap
Hi All, I am trying to do mmap from user space program to fetch physical memory base address B202E7000 and size F0. But I am getting operation not permitted error. Any suggestion by which I can increase the privilage by sysctl to acess this reason ? Krishna
Is this address (0xB202E7000) a memory address or device address ?. R you working as privileged user or a normal user. ? On Fri, Apr 19, 2013 at 11:50 AM, er krishna <erkrishna@gmail.com> wrote:
Hi All,
I am trying to do mmap from user space program to fetch physical memory base address B202E7000 and size F0. But I am getting operation not permitted error. Any suggestion by which I can increase the privilage by sysctl to acess this reason ?
Krishna
-- Regards, Prabhunath G Linux Trainer Bangalore
Root user and trying to acess physical ram reason. I wanted to know is there any limit for mmap through use space and how to override them. Krish On Fri, Apr 19, 2013 at 12:09 PM, Prabhu nath <gprabhunath@gmail.com> wrote:
Is this address (0xB202E7000) a memory address or device address ?. R you working as privileged user or a normal user. ?
On Fri, Apr 19, 2013 at 11:50 AM, er krishna <erkrishna@gmail.com> wrote:
Hi All,
I am trying to do mmap from user space program to fetch physical memory base address B202E7000 and size F0. But I am getting operation not permitted error. Any suggestion by which I can increase the privilage by sysctl to acess this reason ?
Krishna
-- Regards, Prabhunath G Linux Trainer Bangalore
From linux version 2.26.* onwards there is a filter provided by the default kernel configuration disabling the users from accessing the ram area. There was a lengthy discussion on the same topic in this mailing list 2 years back- http://www.spinics.net/lists/newbies/msg41020.html If you still want to access the RAM you disable this option in the kernel configuration menu. *kernel hacking -> Filter access to /dev/mem*.
*Disclaimer:* You will be responsible for the integrity of the RAM contents :) On Fri, Apr 19, 2013 at 12:11 PM, er krishna <erkrishna@gmail.com> wrote:
Root user and trying to acess physical ram reason. I wanted to know is there any limit for mmap through use space and how to override them.
Krish
On Fri, Apr 19, 2013 at 12:09 PM, Prabhu nath <gprabhunath@gmail.com>wrote:
Is this address (0xB202E7000) a memory address or device address ?. R you working as privileged user or a normal user. ?
On Fri, Apr 19, 2013 at 11:50 AM, er krishna <erkrishna@gmail.com> wrote:
Hi All,
I am trying to do mmap from user space program to fetch physical memory base address B202E7000 and size F0. But I am getting operation not permitted error. Any suggestion by which I can increase the privilage by sysctl to acess this reason ?
Krishna
-- Regards, Prabhunath G Linux Trainer Bangalore
-- Regards, Prabhunath G Linux Trainer Bangalore
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