The kernel of operating systems popularly known as Linux, or sometimes GNU/Linux.

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How do I find out what filesystem drivers are compiled-in into the linux kernel?

On a running linux system, what is a portable (among linux distributions) way to find out what filesystems the current kernel has compiled-in (not through modules) support for? Consider for example ...
2
votes
1answer
110 views

Enable BFQ in Fedora

I am running Fedora with the stock kernel and I'd like to enable the BFQ disk I/O scheduler, and ideally BFS. I have built my own kernel and that works, though it is a royal pain dealing with the ...
4
votes
2answers
1k views

USB set to /dev/sda instead of /dev/sdb

I've been trying to use a kickstart file to guide the Red Hat installer (RHEL6.5) without user intervention. It correctly looks for the kickstart file in /dev/sdb/fs.cfg, but because the USB is ...
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0answers
52 views

The latest stable RT patch version of linux kernel 2.6.31

I want to get the lastest stable RT patch version for linux kernel 2.6.31. But I was confused when looking it up at kernel.org. I saw that: patch-2.6.31.6-rt19.gz last modified was on 10-Nov-2009 ...
3
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0answers
39 views

Kernel bisect: when a patch is failing for a reason other than original bisect purpose, what do you do? [closed]

Let's say you're trying to find the cause of a bug between 3.11.0 and 3.12.0. The bug is really difficult to catch, because it may or may not manifest itself over several days of regular workload ...
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1answer
575 views

aircrack-ng shows negative channel

On many Linux distributions, be it BackTrack, Kali, BackBox, Ubuntu, Mint, etc., whenever I use anything from the aircrack-ng suite my wireless card is shown as channel -1. This problem has been ...
1
vote
1answer
69 views

How do I compile source into the kernel?

I want to add and compile my custom application code into my kernel. How should I add my .c and .o files into my kernel 'bin' directory and compile them? I made a hello.c and hello.o file and I want ...
8
votes
1answer
724 views

In what sense does SATA “talk” SCSI? How much is shared between SCSI and ATA?

This is nothing new to me at least, that SATA actually "talks" SCSI, hence why these SATA devices show up as SCSI devices in Linux. A related question has been asked before, e.g. Why do my SATA ...
6
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1answer
137 views

File backed, locked shared memory and disk interaction

Varnish, a HTTP accelerator, uses a ~80MB file backed SHM log that is mlock()ed into memory. The Varnish docs recommend to store the file on tmpfs to avoid unnecessary disk access. However if the ...
2
votes
2answers
236 views

Linux 2.6.36.4, GCC 4.7.2, getting lots of “variable set but not used” warnings

I am trying to compile the Linux kernel 2.6.36.4 on Linux Mint 14 running a 3.5 kernel by default. Using gcc version 4.7.2. Tried googling it, but didn't quite work out. The warning is: warning: ...
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0answers
56 views

Installing linux source [closed]

My distro(Crunchbang) was missing the source files and only the header files were present. So I installed the Linux source using: $ sudo apt-get install linux-source After the completion of ...
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0answers
62 views

SLES 10 SP4 - how to get specific kernel source?

I want to look at the kernel source for some specific kernel versions on SLES 10 SP4. I don't want to see just the Linux kernel source, but the one SLES is actually running. Suppose I wanted to get ...
2
votes
0answers
82 views

Virtual kernel memory layout in dmesg linux kernel 2.6.31

I'm working on a embedded linux project for ARM architecture, kernel version is 2.6.31.12-rt21. In dmesg, I cannot see the virtual kernel memory layout like this: virtual kernel memory layout: ...
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0answers
78 views

inotify does not work with linux kernel 3.4.11

I have a Linux running with kernel 3.4.11. I tried to run inotify-tools, but it does not work (in fact it does not detect the file changes). I checked the .config file of Linux kernel and I found ...
0
votes
1answer
115 views

ncurses-devel problems in SuSE Linux Enterprise Desktop 11

Searching on the WEB, I found this tutorial (the only one that has convinced me) for installing a new kernel and I followed the steps provided. But, I got these problems: In the first step I tried ...
0
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1answer
26 views

kernel config with strange dependancies

I am trying to build the Android Linux kernel from source following this README. The instructions very clearly state: 1.1 Required enabled config options: After building a standard defconfig, ...
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0answers
59 views

Calling speaker-test from usermode-helper API

I needed to call come audio-producing applications from kernel in a toy module. In order to test that, I thought of calling speaker-test from a simpler module, but no sound would ever come from it. I ...
1
vote
1answer
177 views

How is 32bit Linux virtual memory structured in relation to PCIe Base Address Registers

I'm working on a Linux system (32 bit, 4GB RAM) and found some contradictory information about memory addressing in Linux. Am I right with this: Only virtual memory has the differentiation between ...
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vote
0answers
221 views

DisplayPort and Intel HD cause GPU hangs

My system has problems with the displayport connection. This is indicated by several problems that, at the first glance, do not have anything in common. The reason why I claim DP for beeing the cause, ...
0
votes
2answers
144 views

Linux memory usage?

We have 1TB of memory on a server which hosts an SAP application. When the app is running the memory usage shown in top is around 700GB. When the app is stopped the memory usage shown in top comes ...
15
votes
2answers
2k views

Who is responsible for the Linux kernel?

As of today, there are many Linux distributions like Ubuntu, Fedora, Gentoo, Mint, Debian, etc. These distributions update at different cycles. Ubuntu seems to update its kernel weekly or monthly, ...
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2answers
59 views

Running assembly program as ring 0

I'm writing an application which reports back readings from CPU temperature sensors, and the fan speed monitor. However, according to the Intel documentation on PECI, the instructions required must be ...
3
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1answer
255 views

Built the kernel with NFS support but not getting /dev/nfs

I'm trying to build kernel 3.13.9, fetched using apt-get source, and built in a clean debootstrap chroot (both host and chroot being installations of Ubuntu Trusty). My goal is to boot a diskless ...
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0answers
50 views

tasklet and interrupt handler synchronization [closed]

The things I know about tasklet: Tasklet runs with all interrupt enabled. The tasklet runs in interrupt context. It can't sleep. It runs in atomic way. It has the assurance to be scheduled never ...
3
votes
1answer
73 views

Can 32 bit applications on a 64 bit kernel use all the memory?

I know that the 32-Bit kernel can use PAE to allocate more RAM to applications with PAE (up to 64GB) as such I imagine if I am running 32 bit applications on a 32-bit kernel I can use all of my 24GB ...
2
votes
1answer
78 views

I/O schedulers for normal harddisks

For me figuring out what is the best choice for I/O in kernel was a challenge. First I learned that it is subjective then it is depend upon the File-System you use. I know you should use No-op for ...
2
votes
1answer
70 views

View all disabled or hidden linux kernel options

I am trying to build a 3.12 Linux Kernel and I see some of the options (sub menus) are hidden and their branch (menu entry) is disabled in make menuconfig. [---- instead of being --->] I know ...
5
votes
1answer
862 views

What is equivalent to Mac's purge in Linux?

In Mac I use purge to free up some memory. What is equivalent to it in Linux(Ubuntu Server)? apt-get install purge gave me nothing. If you are no familiar with Mac's purge here is it's man page: ...
3
votes
2answers
85 views

Testing the Success of a Congestion Algorithm

How do you test whether a particular congestion algorithm is working for you? I ask because it's not as if I can easily re-create a representative workload for most algorithms. I'm current looking at ...
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0answers
158 views

How do I make strace “decode” AF_NETLINK comminucation like with ioctl?

strace usually "deciphers" ioctls, showing what do they mean, even resolving network interface names and so on. But the same operation performed using AF_NETLINK stays opaque in strace. How to teach ...
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0answers
58 views

What are the two head.S files in linux source ?

In the linux source there are two different head.S files located at: arch/arm/kernel/head.S arch/arm/boot/compressed/head.S What is the puprpose of each one and what is the order of there execution ...
19
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2answers
955 views

What is the purpose of patches of the linux kernel?

For each Linux kernel version, there is a patch file available for download. For instance, linux-3.12.22 has a corresponding patch-3.12.22. What is the purpose of that patch? To always patch the ...
0
votes
1answer
270 views

kernel source code for beaglebone black

I want to build an Ubuntu kernel from scratch for beaglebone black. I have been searching for where I can download the kernel source code for more than two days but haven't found anything. So, ...
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0answers
45 views

Driverless Windows webcam supported by UVC under 3.10 kernel?

There are 'driverless' webcam that plug into Windows 7 and will work directly without driver, in same way as USB finger disk, just plug in and work automatically. Is it true that the mechanism works ...
4
votes
1answer
479 views

Installing linux-3.14.8 un Arch Linux while 3.15 is already in testing

I'm currently running kernel 3.14.6 on Arch Linux from Core repo. I would like to install 3.14.8 (which is the latest of 3.14 series) because it contains a fix that is suitable for me. However linux ...
2
votes
1answer
48 views

Red Hat internal specifications

I'm doing a homework assignment for my college, and I'm trying to find the parameters used in kernel compilation on RedHat. My teacher asks: "Analyse and describes in terms of models of each version ...
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vote
1answer
186 views

Understanding the difference between pid_max, ulimit -u and thread_max

I am trying to understand the Linux processes. I have confusion on the terms pid_max, ulimit -u and thread_max. What exactly is the difference between these terms? Can someone clarify me the ...
2
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0answers
288 views

Server won't boot, kernel panic - not syncing

After a reboot of a CentOS 6.2 server we are getting a kernel panic with the following error: Kernel panic - not syncing: Attempted to kill init! Panic occurred, switching back to text console ...
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0answers
318 views

Why does this iptables rule doesn't get configured after a reboot once in a while? [closed]

On my Android network device, iptables firewall rules service script is started by the init.rc scripts during boot time. One of the firewall INPUT chain rules doesn't get configured in the iptables ...
2
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0answers
122 views

kdump doesn't produce core dump after buggy module is loaded

I am running kernel 3.14.4 on Fedora 18. I am experimenting with a kernel module I am making. The module has a bug (at least one) and crashes the kernel. Sometimes I see a stack trace on my frozen ...
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vote
5answers
166 views

How to find a Linux kernel that works ok on my PC?

I have an old laptop. The newer kernels that ship with the latest versions of the most popular Linux distributions crash from time to time. I want to use a new Linux distribution to get the latest ...
0
votes
0answers
599 views

Kernel 3.14.1 compilation errors

I installed the kernel 3.14.1 and there seem to be no issues. uname -r 3.14.1-031401-generic However, when I try to go to the folder and try to do a make it fails. I see that multiple files are ...
2
votes
1answer
77 views

kernel event listener

I wonder if there is something similar to an event listener in UNIX that a program can subscribe to? Specifically I want to know: Start and end times of a user session Start and end of the ...
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vote
0answers
77 views

Adding IPVS to the kernel

I am trying to setup keepalived on a pair of VPS load balancer servers. I have hit the road block of IPVS not being included with the kernal. IPVS: Can't initialize ipvs: Protocol not available I ...
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votes
0answers
101 views

Extremely slow CD-ROM burning

When I try to burn a CD-ROM using K3B, the burner slows down from 10x to 0.12x after writing exactly 71MB. Consequently, burning a 142MB live CD takes more than a hour. Why is this happening? The ...
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0answers
25 views

booting freezes after used scheduler greatest stack depth error

I have built the linux kernel 3.14 with debug info. When I tried to boot it gives following error and after that booting freezes. Can somebody tell me how to fix this ? Linux Version : Slitaz in ...
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0answers
283 views

Black screen after installing Arch Linux, conventional fixes don't work

I recently installed Arch Linux on my HP Pavilion dv6 (Radeon HD 6770m graphics card) to dual boot with Windows 7 by following the beginner's guide found on the Arch wiki. After grub loads, I choose ...
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vote
1answer
207 views

Library routines in linux kernel

In the linux kernel, there is a section "Library routines" with a snippet shown below: Library routines ---> <M> CRC-CCITT functions <M> CRC ITU-T V.41 functions <M> CRC7 ...
0
votes
1answer
73 views

Why does kernel-devel contain so many “empty” directories?

I have been a Windows kernel developer for many years. Now I start to develop Linux kernel modules. To begin with, I installed kernel-devel under /usr/src/kernels/$(uname -r). However, after checking ...
0
votes
1answer
267 views

custom kernel and firmware loading

After I have compiled my kernel, and when I type make modules_install, not only are the modules copied into /lib/modules/ but also firmware is copied into /lib/firmware/. The following is the end of ...