Everything about UNIX kernels: development, configuration, compilation, design, etc.

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1answer
26 views

Git, Linux kernel and ticketing/bug-reporting

We all know that Linus Trovalds created git because of issues with Bitkeeper. What is not known (at least to me) is, how were issues/tickets/bugs tracked till then. I tried but didn't get anything ...
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2answers
41 views

Which function in Linux kernel do the powering off action?

I am not asking how to shut down. I am asking how to cut of the power. What is the function in Linux kernel code do the action of cutting of the power? And please explain the code.
1
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1answer
19 views

What directory houses the scripts that get executed with new kernel installations?

This one is pretty much a straightfoward question/answer I just can't locate the information. I'm trying to automate the re-installation of VMWare tools based off when a new kernel is installed. I ...
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0answers
13 views

RHEL 6.5 erroneously marking Fusion-io RAID1 card as failed

I am getting the following error every hour for a Fusion-io ioscale2 RAID1 (mirror) configuration. However, the logical volume is mounted and accessible. I do not see similar error in the ...
0
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1answer
33 views

How can I boot into Ubuntu with a linux kernel with an earlier version?

Part of the output of ls -ld /usr/src/linux-headers* on ubuntu 12.04 is: drwxr-xr-x 24 root root 4096 Jun 4 2013 /usr/src/linux-headers-3.2.0-45 drwxr-xr-x 7 root root 4096 Jun 4 2013 ...
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0answers
14 views

How/where are linux device capabilities / bitfields set?

I have a device that has this output in /proc/bus/input/devices: I: Bus=0003 Vendor=05b8 Product=3280 Version=0111 N: Name="PixArt USB Optical Mouse" P: Phys=usb-0000:00:1a.0-1.1/input0 S: ...
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0answers
5 views

How do I set kernel-ml default in CentOS?

I have installed kernel-ml package from http://elrepo.org/tiki/kernel-ml Now I have both the original CentOS kernel and kernel-ml. How do I set kernel-ml as default on boot? Thank you!
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0answers
23 views

iwlwifi: timeout delays firmware to be loaded

I'm using OpenSuSE 13.2 beta (which runs by the way very nicely). When starting up, my wireless adapter (Intel Centrino Ultimate-N 6300 AGN/Thinkpad T420) delays about one minute... But then it works ...
0
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1answer
69 views

yum update returns kernel error

I want to install virtualbox in fedora20. I have followed the instruction here: http://www.if-not-true-then-false.com/2010/install-virtualbox-with-yum-on-fedora-centos-red-hat-rhel/ but when I ...
0
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1answer
26 views

How can I check if a certain patch is already installed in my system?

I am about to install a patch for wireless drivers named Compat Wireless in order to solve a problem with my WiFi channel (it locks on the not existing -1 channel) on my Ubuntu Linux v12.04 and Kali ...
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0answers
31 views

IPTABLES comment: No chain/target/match by that name

Facid with error when adding new rule with 'comment': # iptables -I INPUT 1 --source 66.***.***.78 -j REJECT -m comment --comment "Some" iptables: No chain/target/match by that name. Without ...
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0answers
14 views

Surface Pro Compatible Wireless cards and drivers

In reference to this post: Surface Pro Wifi Issues on Mint KDE 17 there doesn't seem to be any solution to fixing the wifi issues on the Surface Pro when running Linux. The Marvell card doesn't even ...
2
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1answer
44 views

Which Debian kernel should I install?

I've started installing Debian testing on amd64 and I've come to a screen asking me to install a kernel. It gives me a choice between linux-image-3.16-2-amd64, linux-image-amd64, and none. What is ...
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2answers
30 views

Linux Distro name API to get name of linux distro in a driver code?

I am writing a common code in a driver to get the distros name and host name. host name i am taking from struct utsname{nodename[]}, but how do I get the distro name?
2
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1answer
53 views

How to change the kernel max PID number? [duplicate]

The default PID max number is 32768. To get this information type: cat /proc/sys/kernel/pid_max 32768 or sysctl kernel.pid_max kernel.pid_max = 32768 Now, I want to change this number... but I ...
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0answers
17 views

Logging in FreeBSD kernel code [migrated]

I am adding some custom cryptography in the FreeBSD kernel and it causes a panic. I would like to log some variable values in functions that don't appear in the crash files. I used both printf and ...
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0answers
12 views

Monitor/Mwait not working in kernel space [migrated]

I want to test if monitor/mwait works in kernel. So I create a module, inside which two tasks are launched, task2 would call monitor/mwait to sleep. Task1 modify the armed address to wake up task2. ...
0
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1answer
48 views

Role of the Intel P state driver

I searched high and low for what “Intel P state” is and what it does. I found out that it has to do with performance and power consumption. I learned that if you build it in the kernel, it'll becomes ...
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0answers
21 views

How to display printk messages filtered by level as they come?

I wrote a hello word module that performs a printk when it is loaded in level ALERT and another printk when it is released with level INFO: #include <linux/module.h> #include ...
13
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3answers
186 views

How to force Linux kernel to “freeze” (or nearly freeze) for a few hundred milliseconds

We are running a real-time process on a non real-time kernel (CentOS 6), and this is probably not going to change. We have a streaming video application that requires about 500 MB/s of PCIe traffic ...
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0answers
8 views

A question in ip_append_data [migrated]

I am confused with ip_append_data in linux network protocol stack when I see those codes: if (!(rt->u.dst.dev->features&NETIF_F_SG)) { unsigned int off; off = ...
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0answers
26 views

Best approach to adding a kernel driver

I have a task to complete. An LED must be controlled immediately after the kernel loads and into the launch of a Debian system. It also must be controlled in user land. I already have basic LED ...
2
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1answer
33 views

What does kernel-wedge do?

After looking at the package description and using kernel-wedge help, I'm not really sure what it does. Does it take a .deb kernel package and split it into smaller packages? Does it compile a ...
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0answers
16 views

How to recompile official OpenSUSE kernel & initrd?

But it is not okay. I want all of the suse patches applied, I want an official initrd to be generated, and I want to make rpms from all of them. So, I want to recompile the kernel just as the SuSE ...
2
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0answers
44 views

Explanation of the building process of the kernel on Ubuntu/Debian systems

I'm getting into Linux kernel programming and I have successfully built my own kernel several times now. However, I have done it using step by step guides found from the internet and I don't really ...
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0answers
38 views

Fedora 20 won't startup after shutdown during kernel update

I had a few bugs in my System(System Settings not opening and Firefox not starting) and I thought a kernel update(via yum) could do it some good. During that update, I suddenly got logged out as if ...
1
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1answer
49 views

Full UEFI System, Grub 2 self-compiled + Clover 2, Debian kFreeBSD installation?

I've a computer with full installation UEFI system, with 2 bootloaders (GRUB & Clover on ESP) clover is the primary bootloader that allows me to load OSX and grub2. I want to make a new install of ...
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2answers
36 views

Compilation error when building a custom kernel

I'm trying to build a custom kernel from a git repository on my Ubuntu virtual machine. I run the make command as follows : sudo apt-get install vim libncurses5-dev gcc make git exuberant-ctags mkdir ...
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0answers
6 views

How to walk the Kernel's VMA? [migrated]

I'm writing a kernel module that finds and parses the VM_EXEC pages of a process. This is doable through walking the virtual memory of the process, similar to what /proc/$PID/maps does. However, I ...
1
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1answer
31 views

Binding to not existing interface

I've just noticed the very weird situation I don't have a good explanation for. The machine (debian) has one interface with one IP address assigned: # ifconfig vmbr0 |grep inet inet ...
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0answers
18 views

#define SYSCALL_DEFINEx(x, sname, …) [migrated]

In the 3.14 linux kernel there is the following macro : #define SYSCALL_DEFINEx(x, sname, ...) It's located in include/linux/syscalls.h. I added a syscall in the source, I compiled it and I made ...
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0answers
23 views

Linux Oracle - Random crash CPU Stuck

I have several Linux oracle VMs running under hyper-V. Kernel version is 2.6.32-358.el6.x86_64. Sometimes, the VM stuck, we still can ping it, but we cannot ssh, or through the hyper-v console this ...
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0answers
24 views

How build wireless-compat-old in-kernel?

I'm running linux 2.6.24 with custom patches from Freescale, on an embedded board. I want to use a usb wlan modem that uses the Realtek rtl8191su chipset. Realtek provides a driver out of tree, ...
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0answers
36 views

What does `udev` stand for in Linux?

According to wikipedia, "udev is a device manager for the Linux kernel." I just wonder what does udev stand for? Especially, what does the first letter u stand for? userspace or universal?
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1answer
82 views

ZFS support for linux kernel versions 3.16

Attempting to boot Funtoo with a debian-sources-3.16.2-3 kernel, in a system where the root file-system lives in a zpool, drops off to the rescue shell after failing to import the pool properly. Does ...
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0answers
22 views

extract Embedded initramfs

I have a kernel in which one initramfs is embedded. I want to extract it. I got the output x86 boot sector when I do file bzImage I have System.map file for this kernel image. Is there any way to ...
1
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1answer
38 views

How to find the source of a currently running kernel on my machine?

I have a Linux 3.14.0 kernel(CentOS 6.2) running on my machine, but the source isn't in /usr/src/. Is there any way to find out the source from which it was compiled? The source is most definitely ...
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0answers
25 views

Why will plymouth not update?

I admit I don't update my kernel very often. I used to everytime a stable release of sys-kernel/gentoo-sources came out so I'm very adept at doing it. This last weekend I attempted to update from ...
0
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1answer
30 views

Mount JFFS2 FS in openwrt

I'm trying to mount 1[MB] of flash as JFFS2 FS in openwrt environment, using 128[MB] NAND flash (4 bit ECC). I'm using the following sequence - flash_eraseall -j dev/mtd6 mount -t jffs2 -o noatime ...
1
vote
1answer
140 views

Kali Linux - “package has no installation candidate” (also thinkpad-acpi)

I was trying to install the thinkpad-acpi package unsuccesfully, since it had not found the directories needed at all. (no such file or directory response after running the cat ...
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0answers
51 views

yum install kernel-devel: “Nothing to do” [SOLVED]

I need the kernel-devel package to compile a program(How to check if USB WiFi-Adapter is not working or router is out of range?), but when I try to install it via yum, this is the only output: yum ...
0
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1answer
35 views

How to recover firmware on a embedded device with corrupted u-boot and kernel image? [closed]

My embedded device is not working after updating firmware. Thus I tried to update firmware using u-boot. I could successfully get u-boot console via serial connection, but updating firmware failed due ...
0
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0answers
19 views

third party linux auditing software

Linux has a audit system built-in in its kernel and a user space process called auditd reading the system calls intercepted by the kernel. Are there alternate solutions to the Linux Audit system ? I ...
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2answers
45 views

Linux 3.x init ramdisk embedded in bzImage?

Is the initial ramdisk embedded into the bzImage? How to load an rootfs.cpio as a ramdisk and switch the root?
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0answers
60 views

Linux 0.0.1 Kernel - Starting Kernel Programming

To start kernel programming, instead of reading the books, the online references suggested to download the linux 0.0.1 source and find bugs. I have downloaded it and I am going through the code with ...
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1answer
78 views

Real time processes scheduling in Linux

I have been learning some scheduling concepts. Currently my understanding so far is as below. There are real time processes and non real time processes. Non real time processes can have nice values ...
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0answers
19 views

Patching and Compiling my Kernel

So I have an issue with my USB 2.0 ports and I believe I have found a solution for it, which is in the below link. https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1210858/comments/32 I have ...
0
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1answer
207 views

Debian stable: Only GNOME classic with custom 3.16

I compiled a custom 3.16.2 today, which works flawlessly except that GNOME only starts in classic mode. Maybe this is due to changes in the drm i915 driver, but how would I debug this? System is a ...
2
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1answer
45 views

strace works for some builtin commands

I'm trying to understand some kernel level concepts in Linux. I was checking on the difference between shell builtin commands and the other executable commands. This wonderful answer clearly tells ...
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1answer
29 views

rebuilding kernel without using apt-get

I am setting up my Macbook Air 6.2 with Debian Jessie. since I do not have any wireless, I need to set it up manually, but all documentation I find how to do it are using apt-get apt-get install ...