Everything about UNIX kernels: development, configuration, compilation, design, etc.
1
vote
2answers
41 views
What does longterm mean on kernel.org?
It's fairly easy to understand EOL, mainline and stable kernel, but I'm not sure about longterm here,
What does it mean, or how does it differ from stable kernel?
-1
votes
0answers
34 views
create a /proc symlink
I'm trying to build a module using the method shown in this answer.
Basically I need to create a symlink I got it to build, when I try to load it using insmod I get:
-1 invalid module format
and ...
1
vote
1answer
35 views
compressed and uncompressed kernel on an embedded device
I have been using several different embedded boards that store kernel, init files, filesystem, etc. on partitions of a (micro)SD card. I notice in the example usage or instructions that compressed ...
0
votes
1answer
37 views
building/compiling kernel headers
I am compiling kernel 3.4 and 3.8 for different target devices. I would like to install compat wireless driver which requires kernel header. Could anyone tell me how I can compile/build the kernel ...
3
votes
0answers
55 views
How does kernel know, which pages in the virtual address space correspond to a swapped out physical page frame? [migrated]
Consider the following situation: the kernel has exhausted the physical RAM and needs to swap out a page. It picks least recently used page frame and wants to swap its contents out to the disk and ...
1
vote
1answer
39 views
Problem compiling a driver : “No rule to make target”
First of all I am running a CentOS 6.4 installation.
My computer is a laptop and I am trying to install the drivers for my ethernet card, because this week end I lost my ability to connect to the ...
1
vote
1answer
30 views
Virtual mouse driver, possible X11 problems
I created virtual mouse driver according to Essential Linux Device Drivers book. After I wrote coordinates echo x y > /sys/ ... /coordinates into sysfs node, my program generates event packets ...
0
votes
0answers
15 views
Is ZONE_NORMAL mapped on the kernel space only?
In several textbooks I've stumbled upon a strange phrase, that "if the amount of physical RAM available is small, the ZONE_HIGH might not exist at all and all the memory would belong to ZONE_NORMAL".
...
1
vote
1answer
35 views
Excluding kernel modules through /etc/modprobe.d/blacklist.conf does not work
I don't want to load the kernel module nouveau on my debian box at startup, so I put the following in /etc/modprobe.d/blacklist.conf:
blacklist ttm
blacklist drm
blacklist nouveau
I even did a ...
2
votes
1answer
57 views
What is user address space and what is it's purpose?
I am reading about processes. I came across a topic "How a process is created" wherein I encountered the following :-
The process image as viewed by the kernel runs in its own user address space ...
0
votes
1answer
28 views
Assembly files in obj-m list when building kernel modules
I'm trying to build kexec as a module, but I'm running into a weird problem. My obj-m is:
obj-m += kexec.o machine_kexec.o relocate_kernel.o
When I run the makefile, it complains that there's "no ...
1
vote
1answer
40 views
Can kexec be built to a standalone binary, to be used where kexec was not built into the kernel?
I have remote embedded Linux devices I am trying to update to a new kernel without having to physically access. However, the command line options they boot with make one of the MTDs read only - I ...
5
votes
1answer
107 views
How to blacklist a correct bad RAM sector according to MemTest86+ error imdocation?
MemTest86+ (the version included with Ubuntu 13.04) says
Failing address: 002f796c48 - 759.5 MB
What should I specify in the memmap kernel parameter to bypass this area?
I've tried running ...
1
vote
3answers
54 views
What considerations need to be made when choosing the version of kernel for an embedded device?
I have used buildroot to successfully create a kernel, root file system and cross-compilers to enable me to write application code to run on an embedded device. Currently I have no need to write ...
0
votes
1answer
49 views
how to gpio interrupt registering/handling and accessing them from user space in linux [closed]
I am newbie for the linux device drivers please guide me how to do this..
suppose I have connected a switch to one of the controller pin and whenever the switched is press the LED connected to other ...
0
votes
1answer
28 views
debian cannot install kernel source
I want to use debian linux for my laptop again. So I took my old debian 6.0 cds and installed it.
From the last time I know, that I have to build the driver for my Atheros AR8151 Gigabit Ethernet ...
0
votes
0answers
17 views
Nested Linked List in Kernel [closed]
I have a Linux kernel (3.2) module that requires a nested linked list. The main linked list keep track of target programs. For each target program, we need to keep track of another linked list which ...
0
votes
0answers
51 views
*ERROR* timed out waiting for panel to power on
I'm using Ubuntu 13.04 on Asus VX6 (1.8GHz Atom - 2 cores, optimus nVidia ION) with Kernel 3.9.0.
When I start my system I get this error:
[ 15.728106] [drm:intel_enable_lvds] *ERROR* timed out ...
0
votes
0answers
39 views
Decreasing mouse sensitivity at kernel level
I have developed a custom-GUI Server, which runs on virtual console of Linux.For mouse-handling purpose, it reads the mouse device file
/dev/input/mice
and retrieves the event data and updates ...
3
votes
1answer
50 views
Does the vmlinux header contain the length of the kernel image?
I am trying to disassemble a compound file that consists of several parts, one of which is an uncompressed kernel sandwiched between several other files. I am trying to find the exact length of the ...
1
vote
1answer
69 views
Booting encrypted root partion fails after system update
I have a problem booting my Debian Linux server. After a system update, GRUB loads the initrd and the system should ask for the password, but it doesn't. Instead, I get dropped to BusyBox. After ...
2
votes
1answer
36 views
Sign a module after kernel compilation
I've built a kernel in tmpfs, then I rebooted.
Now I see a message when I compile the 3rd party module,
NO SIGN [M] XXXX.ko
How can I get it signed? The key pair generated during rpmbuild is lost ...
-4
votes
2answers
115 views
Why is the UNIX kernel so crucial? [closed]
More specifically, how is the UNIX kernel treated differently from other parts of the Operating System?
0
votes
1answer
30 views
Understanding a XINU system call - getstk.c [closed]
I am having trouble conceptually understanding what is going on towards the end of this system call, and why. I understand the getstk.c method returns the highest memory address of available space, ...
4
votes
1answer
47 views
Making a recovery partition in embedded Linux
I have an Atmel SAM9X system running Angstrom. I am trying to make a recovery partition so when a user holds a button during boot up the recovery partition boots up.
I have modified the bootstrap so ...
7
votes
1answer
141 views
How can I mount filesystems with > 4KB block sizes?
I have a 3TB hard disk pulled out of a WD Mybook Live NAS. The partition table is as follows:
Model: ATA WDC WD30EZRS-11J (scsi)
Disk /dev/sdb: 3001GB
Sector size (logical/physical): 512B/4096B
...
1
vote
2answers
47 views
Does linux modules/drivers belong to kernal space or user space
Some articles say that modules/drivers belong to kernel space as it take part in forming the kernel; (reference: http://www.freesoftwaremagazine.com/articles/drivers_linux)
While others say that ...
0
votes
1answer
34 views
ixgbe: increase rx performance
I have an Intel 82598EB 10GBE NIC.
I need to receive traffic without packet loss.
Data rate is 4-5 Gbps, packet size is 1500-9600 bytes.
I had already configured smb and irq affinity.
I also tried ...
0
votes
0answers
40 views
microphones on apple macbookair1,1
I'm running linux ubuntu 12,04 on a mba. I can't make the microphones (neither external nor internal) work.
Speaking with some wise guys, it seems there is a problem with linux kernel trying to ...
0
votes
0answers
15 views
PID Grabbing Via LSM Hooks
I am grabbing the LSM hooks in my own created module and showing into the securityfs psuedo filesystem which is showing correctly.
The path where these hooks are showing is
...
3
votes
1answer
51 views
How to measure the clock pulse of my computer manually?
My PC has two processors, and I know that each one runs at 1.86 GHz. I have just read about clock cycles and I only have a (very) rough understanding, so I apologize beforehand if my question is so ...
0
votes
1answer
51 views
Enable kernel module for VPN
I'm trying to turn on modules for VPN so I followed this tutorial to compile new ubuntu kernel 3.8.6 .
But the features I've turned on using make menuconfig seem not to be enabled.
(the features I ...
2
votes
2answers
133 views
what is pts/0 and (:0.0) in linux by type who am i
When I type the command:
[root@degeneration Desktop]# who am i
root pts/0 2013-04-12 15:08 (:0.0)
What is pts/0 and what is meant by (:0.0)?
0
votes
2answers
26 views
can't update with this error messg
I got this message:
not enough free disk space.... The upgrade needs a total of 31.8 M
free space on disk '/boot'. Please free at least an additional 31.8 M
of disk space on '/boot'. Empty ...
10
votes
1answer
149 views
Can entropy consumption at program start be prevented?
I use Knoppix (or other Live CDs/DVDs) as a secure environment for creating valuable crypto keys. Unfortunately entropy is a limited resource in such environments. I just noticed that each program ...
0
votes
2answers
151 views
What are “kernel data structures”?
While reading about the Linux kernel I came across the notion of kernel data structures. I tried to find more information via Google, but couldn't find anything.
What are kernel data structures?
...
2
votes
1answer
98 views
Would someone please explain lspci -vv output?
I have the following output from running lspci -vv -s 00:00 on my single board computer running linux.
07:05.0 RAID bus controller: Adaptec AAC-RAID (Rocket) (rev 03)
Subsystem: Adaptec ASR-2230S + ...
1
vote
1answer
53 views
Only output errors / warnings when compile kernel?
When you compile kernel you normally see lines like
CC XX.o or LD XX
So, can I skip these messages? Only output errors or warnings generated by gcc
4
votes
0answers
66 views
Locate occasional CPU kernel hog
I have a 2.6.35 PREEMPT kernel running on moderate-speed ARMv7 processor. About once every 100 - 125s, something causes the kernel to fail to process some audio-related drivers sufficiently quickly to ...
2
votes
2answers
106 views
Why does modinfo say “could not find module”, yet lsmod claims the module is loaded?
According to the man page of lsmod the command shows “what kernel modules are currently loaded”.
I wrote a script that uses modinfo to show what kernel object (.ko) files are actually in use:
...
1
vote
0answers
78 views
Unable to install the selected kernel
I have problem with my DVD drive. It's corrupted and when I'm trying to install Ubuntu it stucks (even with the miniISO)
I was able to successfully start the OS from system rescue CD.
I'd like to ...
0
votes
1answer
62 views
How to troubleshoot high kernel time (high network usage; high interrupts)
I've noticed that I have high kernel time when doing a lot of network traffic in Linux. I also noticed that 45% of my CPU is spent doing interrupts. How can I further troubleshoot this?
0
votes
1answer
56 views
Force Debian kernel version
I need Debian with kernel 2.6.34.8
Is there any way to force Debian with it?
I don't want to install and then compile version I need.
2
votes
2answers
84 views
How is the kernel loaded?
I am trying to understand the Linux boot process, and after reading quite some amount of documentation there is one point that I still can't seem to understand.
So the basicis is BIOS -> Grub MBR -> ...
0
votes
0answers
26 views
Figure out which distro I'm using with Zsh script [duplicate]
I'm making a script that installs some basic needs of mine on my newly installed Linux.
However depending on the Linux distro the contents and commands would be different.
In Arch Linux I would use ...
0
votes
0answers
26 views
How to create a debian 3.x kernel rootfs on a 2.x host
I'm trying to build a rootfs for an embedded A10 board. This will be matched up against 3.0.62+ modules and a corresponding vmlinux image.
I've been trying for a few days to get a rootfs set up for ...
3
votes
0answers
162 views
How do I determine ZCACHE works on my box?
I have an Marwell Kirkwood ARM-based NAS server Zyxel NSA 310. I compiled my own 3.8 kernel and enabled ZCACHE, but I still see 256 MB of RAM. I am not sure if GNU free utility should show extra ...
1
vote
1answer
55 views
Where to start profiling Linux kernel?
What are the standard and conventional ways of profiling the Linux kernel? I know there is perf tool but is there anything else?
1
vote
1answer
54 views
What information exactly is in the access control bits of a page table?
I'm currently learning for an exam in operating systems. This includes learning some basics about page tables, which lead me to the question Why using hierarchical page tables? which mentions that ...
0
votes
1answer
64 views
Relation between the kernel version and OS version
I am running a Ubuntu of version 12.04.
Can I use a kernel of version of version 2.4 on it?
