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

learn more… | top users | synonyms

0
votes
1answer
35 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 ...
4
votes
1answer
789 views

Setting up HDMI output from Linux console

I am currently running Debian Wheezy on a HP Microserver N54L with an AMD Radeon 5450 video card. I would like to be able to play audio from the console through the HDMI port of my video card and ...
0
votes
0answers
20 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
votes
1answer
15 views

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

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
votes
1answer
46 views

auditctl reports “File system watches not supported” on a very old system

When I run auditctl -l I got: # auditctl -l No rules File system watches not supported And I've already have AUDITSYSCALL enable in kernel, # zgrep AUDIT /proc/config.gz CONFIG_AUDIT_ARCH=y ...
0
votes
0answers
18 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 ...
2
votes
1answer
78 views

How to check and set “rhash_entries” parameter?

I'm reading this article, and it says: rhash_entries is the size of the hash table. If you don't specify it on the kernel command line, it is computed dynamically based on the memory available on ...
1
vote
0answers
13 views

Linux 3.x init ramdisk embedded in bzImage?

Is the initial ramdisk embedded in to the bzImage? How to load an rootfs.cpio as a ramdisk and switch the root?
1
vote
0answers
19 views

Understanding IRQs usage [migrated]

In the last couple of days, I've trying to implement a simple interrupt handler in C. So far so good, I think I've achieved my initial task. My ultimate goal is to inject some faults in the kernel ...
1
vote
0answers
46 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 ...
2
votes
2answers
1k views

SCTP support for Linux kernel 3.3.4-5.fc17.x86_64

I'm using Fedora 17 64-bit version, with Linux kernel version 3.3.4-5.fc17.x86_64. I installed lksctp using yum. sudo yum install lksctp-tools.x86_64 When I try to run sctp_status -H 127.0.0.1 ...
3
votes
1answer
6 views

Real-time executive approach, can be run in desktop Linux?

With the real-time executive approach, a small real-time kernel coexists with the Linux kernel. This real-time core uses a simple real-time executive that runs the non-real-time Linux kernel as its ...
1
vote
1answer
34 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 ...
0
votes
0answers
18 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
votes
0answers
23 views

Is a monolithic kernel more secure than a microkernel? [closed]

I don't know much about what microkernels can do so bear with me if I'm being ignorant: In one instance, there are monolithic kernels which allow the user control over services before reaching ...
1
vote
0answers
138 views

Some questions compiling linux kernel with make-kpkg

I'm doing my first steps compiling the linux kernel and adding a new system call. I've managed to do it, but I still have some questions. For this task, I has set up a Virtual Machine guesting debian ...
2
votes
1answer
898 views

Scaling issues of i7 3520M with intel_pstate module on Kernel 3.10.0

Few days ago I updated my openSUSE 12.3 system from Kernel 3.9.8-1.gf3348a8-desktop to 3.10.0-1.g3dcd746-desktop and since then, turbo mode of my i7 3520M is enabled by default and it does not ...
1
vote
2answers
539 views

running kernel on QEMU

I face this message: Failed to execute /initKernel panic - not syncing: no init found. Try passing init=option to kernel. I am using this command line: qemu-system-x86_64 -hda disk.img -kernel ...
2
votes
1answer
33 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 ...
5
votes
1answer
340 views

Loading speedstep_centrino kernel module

Because of a noisy fan in my laptop, I need to change CPU frequency and for this task I need to load the appropriate kernel module. The CPU in my laptop Acer TravelMate 4002WLMi is: $ cat ...
1
vote
1answer
274 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 ...
4
votes
3answers
6k views

Cleaning log files under linux

I am using a kvm ubuntu 10.04 virtual machine to test some features of a kernel module. I grep through the /var/log files to observe the kernel messages about that module. To start from a clean ...
6
votes
2answers
681 views

Asus X101H - Touchpad not recognized (want to disable while typing)

I have been struggling with this issue for a while and have done an exhaustive search for answers here and elsewhere before posting this question. On my Asus X101H, the touchpad is not recognized as ...
1
vote
1answer
2k views

How to get back from “testing” to “stable” - Kernel downgrade

currently I am having lot's of fun with apt-get - and the bad thing is, it was my own fault. I had enabled the testing packages in /etc/apt/sources.list to install a certain package. And I told my ...
1
vote
1answer
24 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 ...
0
votes
0answers
43 views

USB Keyboard Hotplug Module not Working

The following module could be compiled and loaded without any error: #include <linux/module.h> #include <linux/kernel.h> #include <linux/usb.h> #include <linux/usb/input.h> ...
3
votes
3answers
170 views

Compare two kernel config files from the menuconfig perspective?

I have a situation in which i have two kernel config files (for the same kernel source ). Both of them have a part of the functionality that i need (on one, USB works correctly, on other, the second ...
0
votes
1answer
1k views

bnx2: Can't load firmware file “bnx2/bnx2-mips-09-6.2.1b.fw”

I just compile the kernel 3.10.19 from kernel.org Support for bnx2 is enable. On my server when I try to start the eth0 interface I got the following error : bnx2: Can't load firmware file ...
6
votes
5answers
2k views

Given a kernel ATA exception, how to determine which physical disk is affected?

I woke up this morning to a notification email with some rather disturbing system log entries. Dec 2 04:27:01 yeono kernel: [459438.816058] ata2.00: exception Emask 0x0 SAct 0xf SErr 0x0 action 0x6 ...
0
votes
1answer
412 views

modpost.h:12:23: fatal error: elfconfig.h: No such file or directory

I am running Ubuntu: #lsb_release -a No LSB modules are available. Distributor ID: Ubuntu Description: Ubuntu 12.04.4 LTS Release: 12.04 Codename: precise Kernel info: 3.8.0-38-generic ...
2
votes
1answer
97 views

What does the CONFIG_NLS_UTF8 kernel option do?

The kernel configuration contains an NLS_UTF8 option. It can be found under File systems → Native language support. What does it do? Its description maintains that it is needed for using a FAT or ...
3
votes
1answer
1k views

After installing a new Kernel in Ubuntu 14.04, rebooting takes me to busybox initramfs. How do I mount a filesystem after that?

I have a virtual machine with Ubuntu 14.04 in it. I recently built and installed linux-3.14.5 kernel on it, and tried to boot into it, but it drops me to BusyBox v1.21.1 built-in shell. Here's what I ...
3
votes
1answer
655 views

Kernel booting stops right after “Uncompressing Linux…”

I'm trying to bring up an ARM-based board. I've got U-Boot working but can't seem to get the kernel to load. Most of the time it only goes as far as: Starting kernel ... Uncompressing Linux... A ...
1
vote
1answer
493 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 ...
1
vote
1answer
395 views

Why system call hooking produces different result everytime in Linux/Android 2.6.29?

I have implemented system call hooking for Android 2.6.29 kernel through a LKM module. I am tracing down one Android app for system calls. But interestingly, it returns different results every time I ...
2
votes
2answers
724 views

busybox initramfs loop mount

I'm trying to loop mount my root filesystem (a loop file) within a busybox initramfs. I try to run the command: mount /rootfs.raw /root ... which works on my Ubuntu laptop, however, I simply get ...
4
votes
3answers
4k views

mount.cifs : mount error(12) : Cannot allocate memory

I encountered this problem a while ago when upgrading my kernel but put off upgrading until now. On my system I can happily mount network shares using CIFS running kernel 3.7.10, however when I've ...
1
vote
1answer
2k views

How to fix unreliable Realtek Wireless card on Ubuntu 13.04

I have a Realtek RTL8188CE wireless card and it works fine when I have a strong signal, but if I get even slightly away from the wifi I lose connectivity even though there is a strong Rx signal. I ...
2
votes
0answers
30 views

Why does each process folder under /proc contain the same information?

Under /proc/<PID>/net pseudo-file system each process seems to have files with the same content. For example I use cat /proc/<PID>/net/ip_tables_names to list iptables tables under the ...
17
votes
3answers
828 views

What are the responsibilities of each Pseudo-Terminal (PTY) component (software, master side, slave side)?

I am trying to figure out how a tty works1 (the work-flow and responsibilities of each elements). I have read several interesting articles about it, but there are still some blurry areas. This is ...
2
votes
1answer
323 views

Kernel headers for VMware tools

I tried to compile VMware tools on my server. I compiled the kernel myself, I didn't use RPM. As VMware tools needs the kernel header files, I executed the following command in my kernel folder ...
-1
votes
0answers
47 views

Linux crashes when i attach usb dongle

I have a D-Link Usb dongle the description about it is: $ lsusb | grep D-Link Bus 002 Device 003: ID 07d1:3303 D-Link System DWA-131 802.11n Wireless N Nano Adapter(rev.A1) [Realtek RTL8192SU] My ...
0
votes
0answers
24 views

how to limit dma address to specific range in linux kernel?

I want to limit the dma address the device can access to 0x0100_0000~0x03ff_ffff. But I don't know how to set the dma_mask and coherent_dma_mask. It's easy to set the "dma mask" for a range start ...
1
vote
1answer
91 views

How does bash execute an ELF file?

When I'm on my Linux Box I use bash as a shell. Now I wondered how bash handles the execution of an ELF file, that is when I type ./program and program is an ELF file. I grepped the bash-4.3.tar.gz, ...
0
votes
0answers
33 views

Noob Kernel Image Question

I'm playing about with CM-FX6 , an iMX6 based SOC. The chip comes with the following: http://www.compulab.co.il/workspace/mediawiki/index.php5/CM-FX6:_Linux:_Kernel **images** uImage-cm-fx6 - ready ...
2
votes
0answers
28 views

Why is there no rootfs file system present on my system?

The linux kernel documentation claims: Rootfs is a special instance of ramfs (or tmpfs, if that's enabled), which is always present in 2.6 systems. You can't unmount rootfs … On all linux ...
1
vote
1answer
40 views

Booting into a kernel image

I have a recently-compiled Linux kernel image (vmlinuz file) and I want to boot into it. I am aware that this won't give me a familiar Linux system, but I am hoping to be able to at least run some ...
2
votes
2answers
732 views

Linux freezing guess: keyboard & mouse (Archlinux and Ubuntu)

Linux on my PC is freezing a few seconds after startup. I am unable to use the mouse / keyboard. Neither Ubuntu nor Arch do anything after a few seconds. Windows has been running fine for years now. ...
3
votes
2answers
435 views

Linux: Is there a IPv6 equivalent to the IPv4 kernel option accept_local?

Since linux kernel >= 2.6.33 the kernel option "accept_local" can be modified: /proc/sys/net/ipv4/conf/${interfaceID}/ accept_local - BOOLEAN Accept packets with local source addresses. ...
1
vote
3answers
902 views

Why kernel 3.6.2 is so much less energy efficient than 3.6.1 on Mint 13?

I noticed, that the power consumption in my ASUS P53E notebook is doubled (from 10W to 20W) when I change from kernel 3.6.1 to 3.6.2 (or later). I use Ubuntu Quantal mainline kernel from ...