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

learn more… | top users | synonyms

1
vote
0answers
4 views

Having problems with negative monitor channel, intimidated!

When I try this command: aireplay-ng -1 0 mon0 -a xx:xx:xx:xx:xx:xx I get this output: No source MAC (-h) specified. Using the device MAC (xx:xx:xx:xx:xx:xx) 17:51:23 Waiting for beacon frame ...
0
votes
0answers
4 views

Why doesn't mmc_spi.c allow highmem? [migrated]

I would like to use the Linux mmc_spi on a system with highmem enabled. I can't see why the mmc_spi module won't work with highmem. The module uses kmap() and kmalloc(), so I am unsure as to why high ...
0
votes
0answers
58 views

Ubuntu: freezing on startup

I recently installed Ubuntu 14.04 on a new ThinkPad laptop as a dual boot with Windows 8. It has been running for a few days without issue. However, when I booted my computer today, it got stuck on ...
4
votes
1answer
32 views

What is a sync during kernel boot?

If something prevents a Linux system from booting, it is common to see this message: kernel panic - not syncing: [Error Message] But what does "not syncing" mean? What exactly isn't syncing? The ...
6
votes
4answers
579 views

Is it possible to tell if my Linux kernel is custom (i.e. compiled) as opposed to distro?

Taking example of Ubuntu, can we tell if the kernel was custom compiled rather than what comes with distro?
1
vote
0answers
12 views

Understand Linux kernel virtual bridge port numbering

I have a Linux kernel virtual bridge which contains interfaces eth1 and tap0: # brctl show br0 bridge name bridge id STP enabled interfaces br0 8000.00016c404fa3 ...
2
votes
1answer
48 views

Debian: How to get the current loaded kernel package name?

With the following command, I can list all the installed kernel package: $ dpkg -l | grep linux-image With the following command, I get for instance the version of the current kernel used: $ uname ...
1
vote
1answer
21 views

What do the terms CC, LD and SHIPPED refer to during the Kernel Source compilation process?

What do the terms CC, LD and SHIPPED refer to during the Kernel Source compilation process? Am I correct to assume that [M] indicates that it is being compiled as a module?
1
vote
1answer
45 views

What proportion of memory does the Linux kernel use of the installed RAM?

I'm developing a compute cluster and I'm trying to determine the maximum amount of RAM I can give to a single process. On a machine with 16GB of ram, the answer is that I can allocate (and touch) ...
0
votes
0answers
36 views

How to artificially cause a page fault in Linux kernel? [migrated]

I am pretty new to the Linux kernel. I would like to make the kernel fault every time a specified page 'P' is being fetched. One simple conceptual idea is to clear the bit indicating the presence of ...
1
vote
1answer
21 views

XFRM_SUB_POLICY config in kerne

When testing strongswan performance, we saw that the performance differed by a lot between an ubuntu server and a centos server, with everything else being the same. We noticed that the ...
1
vote
1answer
19 views

How do I understand if an USB Ethernet adapter is compatible with a certain kernel version to use it to load kernel/filesystem?

I'm using an old kernel, 2.6.32, and I would like to boot the kernel over TFTP and mount the filesystem over NFS. Mounting the kernel over TFTP is a plus, but mounting the filesystem over NFS is a ...
0
votes
0answers
13 views

shm.h header file not found in Linux 3.13.3 [migrated]

I am new to for Linux. I have downloaded Linux 3.13.3 and I am trying to make a system call for shared memory. I have created a "hello world" system call and it runs perfectly. When I compile my ...
0
votes
0answers
17 views

Continuety of driver support in linux kernel

I am an embedded GNU/Linux learner. I understand with the new Kernel, driver support for most added hardware is coming through Device Tree Structure (DTS). But I have found out that there are still ...
1
vote
0answers
18 views

Find the creator of a task

I would like to find the creator task of an arbitrary task in the Linux kernel. However, I am not sure, if there is a way to do this in general. Normally, you can find the creator of a task via the ...
0
votes
1answer
15 views

Install kernel .deb file without using dpkg

I'm running Manjaro (Derived from Arch). I have a .deb file for kernel 4.0. Is it possible to install the kernel from this file, and what are the steps involved? I tried opening the .deb file and ...
2
votes
1answer
20 views

add key to proc/keys

How do I add a key to a keyring in /proc/keys ? My openembedded Linux does not come with a keyctl command program. And all I can find on google is the programming interface, but I would like to do ...
1
vote
1answer
44 views

what if I uninstall all linux kernel images from my system

If I run this: sudo apt-get purge linux-image-* this will definitely remove all linux kernels images from my system. so the question is will I be able to use my system normally until I reboot or ...
0
votes
1answer
53 views

How can I edit /proc/net/tcp?

I need to edit 1 line in /proc/net/tcp while the file is also used by the linux kernel for updating other lines of it by the kernel. Background: Each line in /proc/net/tcp represents a TCP socket. ...
2
votes
1answer
67 views

Device eth0 does not seem to be present, delaying initialization

I have cloned a fedora and now trying to configure network interfaces. Every time i am adding a new NIC, it starts with number eth3 (rather eth0). i have tried removing and modifying the ...
1
vote
1answer
47 views

What happened after I upgraded the kernel version?

I have Linux Mint 17.1 Cinnamon version on my notebook HP Compaq 15-h050nl and about 1 month ago I upgraded the Linux Kernels to the current version (3.18.2-031802-generic) from the last version. ...
0
votes
0answers
15 views

centos 7 installation with customized bridge module

I have installed latest Centos 7 x64 edition in my server. I need to modify the linux-bridge module with some customized changes and use it as a default bridge module. Currently I am building centos ...
0
votes
1answer
51 views

Getting error virtualbox-guest-modules: requires linux<4.0 on antergos while doing system upgrade

I am running Antergos Linux 64 bit on virtual box. when I try to do full system upgrade I get a error: resolving dependencies... looking for conflicting packages... error: failed to prepare ...
0
votes
0answers
25 views

How to write your own exception/interrupt handler? [migrated]

Any simple and basic example to write the exception? I've been searching the web for the past few days. Couldn't find any good site. :/ I got this as an assignment - Write an "Assembly handler" ...
1
vote
2answers
38 views

Identify out of tree modules?

I'm attempting to upgrade and test kernel 3.12. What is the most efficient way to identify out-of-tree modules that should be removed before testing? There are a few mentioned (vitualbox, nvidia, ...
0
votes
0answers
14 views

“un-select” behavior in kconfig

Are there any ways to generate the behavior of an "un-select" over an option? I don't want the option to disappear ("depends on" behavior), but just the opposite behavior of "select". Thank you very ...
1
vote
0answers
11 views

TCP retransmission for the same packet but with the different TCP payload [migrated]

I'm developing an Ethernet driver in Linux platform. I found that when a TCP retransmission occurred, the TCP payloads of multiple retransmission packets referring to the same sequence number packets ...
0
votes
1answer
20 views

Kernel Firmware for Radeon

I'm building LFS. I was trying to enable Ati radeon drivers in the kernel, but it didn't seem to work, so I did a little Googling and found that the there is something called firmware which the kernel ...
0
votes
0answers
13 views

installing r8168 driver in centos 4.8

I have installed cent os 4.8 and I am not able to connect to internet from that system. After searching on the net I found that the system has r8169 driver instead of r8168. Now I am trying to ...
0
votes
0answers
13 views

Different types of pageouts - Data?

In Linux, pageouts are controlled by the following properties /proc/sys/vm/dirty_expire_centiseconds /proc/sys/vm/dirty_background_ratio /proc/sys/vm/dirty_ratio Thus pageouts can happen due to ...
2
votes
1answer
46 views

Linux kernel action upon init process exiting

Say I am writing my own init program running on a Linux kernel. What happens when my init program exits with return value 0 ? Additionally is the behaviour different if the return value is non-zero? ...
-1
votes
0answers
18 views

Is netcat or socat zero copy

netcat or socat could run like a broker in messaging systems. For example: a one-line forward server socat TCP4-LISTEN:www,fork TCP4:www.domain.org:www Are they zero-copy under the hood?
1
vote
0answers
17 views

how to set or know scaling driver in linux kernel

I am trying to modify the scheduler/governor. For the same I need to know what CPUFreq Driver or scalling driver am I configured to run. 1.Where can I find what scaling driver am I configured to ...
0
votes
1answer
25 views

Find SAS controller that is well supported by the linux kernel

How can I find a SAS controller that is well supported by the official Linux kernel? The controller should use the PCIe bus and needs to connect one LTO-6 tape drive. I have looked through the ...
6
votes
2answers
82 views

Besides cache, what does the Linux kernel use significant amounts of memory for?

My computer feels really sluggish. According to free, I have only ~200M RAM left and more than a gigabyte had to be swapped out. I know that it is good if memory is used for caching but this looks ...
0
votes
0answers
13 views

Starting Kdump: FAILED

I am unable to start kdump on my machine. It is prompting Starting Kdump: FAILED. I have edited the /etc/grub.conf file and provide 1024M to crashkernel. I have also provided the path to where the ...
0
votes
0answers
6 views

Is that safe to use kfifo (not a _spinlock flavour) in fiq/nmi handlers? [migrated]

Basically need to pass variable-size records to and from FIQ handler (ARM platform). During any get/put operation on kfifo (on the user-space/kernel side only) I am going to disable all IRQs and ...
2
votes
0answers
282 views

Can I make the boot even more verbose than loglevel=7 using kernel parameters?

I have an error when booting on a machine, my machine is stuck with the error message: Booting a command list. I can see this message when I add loglevel=7to the kernel parameters via grub boot ...
0
votes
1answer
38 views

How to select the tag of the latest non-unstable/release candidate version?

I've downloaded the latest kernel sources: git clone git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git cd linux-stable git tag -l | less and picked v3.9.1. git checkout -b ...
1
vote
1answer
71 views

Linux Kernel Live Patching - WHATIS and HOWTO?

I am trying to understand a new concept I got to know recently as the Linux 4.0 makes it way to the mainline - "Live Patching". Supposedly this is a new feature enhancement of the Linux kernel. It ...
0
votes
0answers
36 views

Repackage RPM with kernel

I am tinkering with CentOS 5.4 and upgrading the kernel to the latest 2.6.18 build 402. What I need to do is to rebuild the initrd to include a modified init script, then repackage it all into an RPM ...
0
votes
0answers
27 views

isolcpus doesn't work on Ubuntu 14

I added isolcpus=0 to the end of the following line to the file /etc/default/grub GRUB_CMDLINE_LINUX_DEFAULT="quiet splash isolcpus=0" The idea, as I understand it, is to reserve core 0 from having ...
0
votes
1answer
56 views

Upgrading guidance for Cedarview driver in Debian 6 - 2.6.32

Our system runs with Debian 6 squeeze (2.6.32) Kernel with N2600 hardware. I know the version is old. An upgrade is in later plans. Recently, we tried connecting multiple monitors (CRT and HDMI), and ...
0
votes
0answers
49 views

Tegra Mesa GLES without X

I am trying to setup a Tegra 3 (Toradex Apalis T30) based system that will have an OpenGL ES based user interface on a touch screen. Unfortunately the standard Linux4Tegra kernel is seriously outdated ...
0
votes
1answer
32 views

Is the PTTY inside the Kernel or Userspace?

I read, that drivers are a way to expand the Kernels abilities to communicate with hardware devices, since there are so many and will be even more the Kernel has to be expandable. In order to ...
1
vote
0answers
36 views

How to set SyslogIdentifier in [SERVICE] section of systemd service file as empty?

I want to set SyslogIdentifier in [SERVICE] section of systemd service file as empty, so that nothing is prefixed in the logs. I tried below options: 1) Mentioning nothing: SyslogIdentifier= ...
0
votes
0answers
41 views

Yocto menuconfig not working

For some reason the menuconfig menu does not come up when I try launching it from my Yocto installation. I am using the Toradex Yocto 1.6 system as is described here ...
0
votes
1answer
34 views

What is a Kernel Routine ?

In another answer I met a short overview of the sections of the man pages: commands for $-User system call, that means evoking a function from the Kernel library call, that means evoking a function ...
3
votes
1answer
251 views

Does Linux virtual bridge support VLAN's?

Does Linux virtual bridge(configured with for example ip or brctl) support VLAN's? For example configure access ports in different VLAN's and trunk ports with only certain VLAN's enabled. Only option ...
1
vote
1answer
32 views

web cam starting hangs os

I faced a strange effect as ... when my notebook wakes up from suspend I can start and close my web cam with guvcview 1-3 times; But after while on 3dr or 4th starting attempt (I didn't count for ...