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

learn more… | top users | synonyms

2
votes
0answers
20 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
689 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
319 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 ...
0
votes
0answers
22 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
11 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
61 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
25 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
24 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
25 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
486 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
424 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
901 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 ...
1
vote
3answers
110 views

How to install/make the kernel section 9 manpages which document its functions and data structures?

The kernel sources contain functions and data structures which are documented, for instance in panic.c: /** * panic - halt the system * @fmt: The text string to print * * Display a message, ...
1
vote
1answer
55 views

How do I compile the linux kernel version 3.16.1 to run in Slackware 14.1?

Could someone teach me or give me some tutorial? How do I compile the linux kernel version 3.16.1 to run in Slackware 14.1.
0
votes
0answers
9 views

LVM2 Mirror Support Missing from Kernel after System Migration

I had a system that was running on a small netbook that had LVM2 set up to group two external USB hard drives into a volume group, and to use that volume group to create a mirrored logical volume. ...
8
votes
2answers
5k views

What is the difference between the following kernel Makefile terms: vmlinux, vmlinuz, vmlinux.bin, zimage & bzimage?

While browsing through the Kernel Makefiles, i found these terms. So i would like to know what is the difference between vmlinux, vmlinuz, vmlinux.bin, zimage & bzimage?
6
votes
1answer
10 views

Linux kernel 3.10.0-123.4.2 processes [flush] aren't present

I am using CentOS 7 with "3.10.0-123.4.2.el7.x86_64" version, but I don't know why the kernel threads named flush aren't present in this kernel version. I tried to look in the kernel change log, but ...
4
votes
2answers
752 views

Benefiting of sched_autogroup_enabled on the desktop

I am running a 2.6.37 kernel with sched_autogroup_enabled set to 1. I am not certain that I am seeing the benefits of this patch since: I am launching my applications from the desktop; applications ...
2
votes
2answers
1k views

After upgrading the kernel, the sound no longer works

I have updated the Linux kernel on my system to Linux 3.11-2-amd64 #1 SMP Debian 3.11.10-1 (2013-12-04) x86_64 GNU/Linux. Having done that, the sound no longer works. Distribution Info(cat ...
2
votes
2answers
88 views

Detecting kernel thread on pre-3.0 kernels

Looking at the proc man page (http://man7.org/linux/man-pages/man5/proc.5.html) it is possible to detect which processes are kernel threads in /proc/<pid>/stat by looking at the flags value ...
1
vote
0answers
25 views

drm Kernel v>3.11 Issues

Just a regular Fedora 20 user here (coming from no answers on ask.fedoraproject.org). I'm having some issues with the most recent kernel versions. The last working (no black line) kernel I have ...
0
votes
0answers
17 views

Generate what a GRUB2 kernel line would look like

In GRUB 0.97 we were able to see what the kernel line/options would look like by just viewing /boot/grub/grub.conf. Now the only way I know how to check the next boot kernel options/kernel version ...
4
votes
1answer
587 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 ...
1
vote
1answer
40 views

sysrq-trigger doesn't accept parameter 'g'

I'm trying to debug the kernel. But I couldn't trigger kgdb with echo g > /proc/sysrq-trigger, it just prints help message. I have enabled kernel debugging, kgdb over serial, frame pointer etc. ...
1
vote
0answers
14 views

Kexec immediately after Kickstart install (where is cmdline?)

I used to be able to kexec into a new kernel immediately after a kickstart (anaconda) install via pxe. I was able to do this by figuring out the current kernel version, and grabbing cmdline options ...
0
votes
0answers
19 views

Warning for kernel “make config” command without sudo

while trying to configure kernel before compile, when I give this command without sudo privileges: make config I get these: /boot/config-3.2.0-4-amd64:488:warning: symbol value 'm' invalid for ...
16
votes
1answer
10k views

How do you empty the buffers and cache on a Linux system?

Prior to doing some benchmarking work how would one free up the memory (RAM) that the Linux Kernel is consuming for its buffers and cache?
2
votes
1answer
20 views

Installing a new OpenBSD kernel “safely”: why does `make install` go through these extra hoops?

After building a new OpenBSD kernel, the install target of the kernel Makefile does the following: rm -f /obsd ln /bsd /obsd cp bsd /nbsd mv /nbsd /bsd I understand that the first two lines remove ...
1
vote
0answers
23 views

“disagrees about version” message

I get a message "disagrees about version" on boot time, after compiling kernel and modules with KGDB. Why should this happen ? Is there any problem with KGDB ? This is the relevant log at boot: ...
0
votes
2answers
433 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 ...
0
votes
0answers
47 views

Resume from Suspend/Hibernate issues

I have a peculiar problem while trying to resume from both suspend and hibernate. I believe the problem to be within the kernel itself since I have tried different distros (Ubuntu, Suse, Mageia) on ...
2
votes
1answer
6k views

/lib/modules/2.6.37.6/build missing in linux puppy? what should I do?

I am new to linux as of yesterday. I'm using linux puppy to try to get the most out of a 10 year old, slow laptop. I installed it fine, no problems there, but as soon as I try to use my usb dongle's ...
3
votes
1answer
395 views

What happened to `vga=ask` in newer kernels?

I used to activate framebuffer mode in the "older" kernels with vga=ask, and later setting it to a value, once I've figured out which one works best for me. Now, this option seems to be gone, the ...
0
votes
0answers
17 views

How to boot on a ramdisk?

I'm working on a linux embedded for a custom board with a ARM9 processor. My kernel version is : 2.6.33 I'm trying to boot on a ramdisk, kernel correctly mount the file system but failed to execute ...
1
vote
1answer
801 views

Apt-Get Install Unmet Dependencies

My debian computer will not install the new kernel. It says I have unmet dependencies, and those dependencies say they have unmet dependencies. Many of these dependencies are already installed ...
1
vote
0answers
38 views

What does __ prefix before some kernel api's convey?

Why do some function calls in kernel specially have this prefix __ example: __init initialization(void) is __init a macro? What does this convey? Are these a special class of function calls inside ...
7
votes
1answer
424 views

How pipes work in Linux

I've been reading up about how pipes are implemented in the Linux kernel and wanted to validate my understanding. If I'm incorrect, the answer with the correct explanation will be selected. Linux ...
1
vote
1answer
31 views

/proc/config.gz is of 0 bytes

I have an Android TV stck I compiled Linux for IT from https://github.com/Galland/rk3x_kernel_3.0.36 But when I booted that Image I found /proc/config.gz is of 0 bytes can some please explain how ...
11
votes
3answers
582 views

Contents of /proc

Is there a site someplace that lists the contents of /proc and what each entry means?
6
votes
2answers
673 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 ...
3
votes
1answer
25 views

eCryptfs key in kernel image or initramfs

I have an embedded Linux system with unencrypted kernel image and initramfs in NAND flash. My RootFS is in SD card. I want to encrypted some files on SD Card as my SD card is easily accessible ...
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 ...
0
votes
0answers
11 views

Module load map

How can I obtain a module load map? I've tried with the -m flag in insmod but it seems that since 2.6 there is no support for it. Thanks
1
vote
0answers
59 views

kernel log in /var/log/messages: task xxx blocked blocked for more than 120 seconds . System frozen

Monit sent out emails in the morning that my java app on the server was not responding to HTTP calls made on the 127.0.0.1 interface. App log shows nothing out of the ordinary, nginx log shows no ...
5
votes
1answer
334 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 ...
7
votes
3answers
4k views

Can vmlinux be used instead of uImage?

I want to use an uncompressed kernel image and boot the BeagleBoard. Generally I use uImage to boot the kernel which is in compressed format. How do I use an uncompressed kernel image?
0
votes
1answer
31 views

install kernel headers without overwriting old headers

I've built a newer (3.16-rc2) kernel which is running fine. My userspace program needs to link against the newer headers as it uses some new definitions in fcntrl.h etc. My question is how do I ...
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 ...
0
votes
2answers
49 views

Error Installinig Kernel on Centos (from Source)

I am running GNU/Linux (Centos 6) on kernel 2.6.32-431.17.1.el6.x86_64. I am trying to update the kernel to 3.2.61. I performed the following steps inside the 3.2.61 folder structure: make ...
2
votes
2answers
199 views

IPv6 NDP timer problem

Need to change Fedora Linux's IPv6 stack for NDP DAD timer changes. How to locate the Fedora's IPv6 and IPv4 stack in Fedora distribution dvd/site so that, we can recompile and generate new stack ?