Tagged Questions

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

learn more… | top users | synonyms

0
votes
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
votes
1answer
220 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
votes
1answer
47 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 ...
1
vote
1answer
30 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
69 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> ...
2
votes
0answers
35 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 ...
0
votes
0answers
29 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 ...
0
votes
0answers
60 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
33 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
44 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
1answer
305 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
16 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. ...
3
votes
1answer
14 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
218 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.
6
votes
1answer
55 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 ...
0
votes
0answers
21 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 ...
1
vote
0answers
88 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 ...
1
vote
0answers
25 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
50 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 ...
2
votes
1answer
32 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
28 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
0answers
103 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 ...
0
votes
0answers
41 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
0answers
50 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 ...
1
vote
3answers
174 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, ...
8
votes
1answer
732 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
52 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 ...
3
votes
1answer
60 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
0answers
22 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
215 views

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

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 ...
0
votes
1answer
38 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 ...
0
votes
2answers
130 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 ...
1
vote
1answer
92 views

Is it possible to use XNU on GNU/Linux?

I was wondering whether it is possible to use the XNU kernel on a GNU/Linux system? But it would be, in effect, GNU/XNU. But is that possible? Does the kernel have sufficient drivers to boot on a ...
1
vote
2answers
757 views

CentOS ELRepo Kernel installing VMware

Already installed VMware Workstation 9 on my Linux CentOS 6.5 Final with 3.10.40-1.el6.elrepo.x86_64 running kernel. When I open VMware Workstation, it asks me to locate the Kernel Headers ...
2
votes
1answer
32 views

How do you patch a kernel? [duplicate]

I got diff text from lkml how do I patch it into a kernel source? I am very new to compiling kernels, and I couldn't find decent sources online I am using debian if it is relevant
3
votes
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 ...
0
votes
0answers
523 views

nfsd fails to start: modprobe: FATAL: Could not load /lib/modules/2.6.18-238.1.1.el5/modules.dep: No such file or directory

Before asking, here are some system specs: [root@SERVER ~]# cat /etc/*release **##############CARS build log for cars20-rhel-x86_64############## Date: Mon Feb 28 20:06:05 PST 2011 Builder: ...
1
vote
0answers
26 views

CPUFreq Kernel module

I would like to try the CPUFreq module on my board (Marvell Soc based on ARMv7 running a v3.15 linux kernel). My architecture is obviously not supported by the default source code (located in the ...
1
vote
1answer
58 views

Which kernel module name is currently correct “usb-storage” or “usb_storage”?

I have found a number of examples how to prevent a kernel module from being loaded. One of them is about USB storage module. The next code has been provided: echo "blacklist usb-storage" | sudo tee ...
5
votes
2answers
2k views

Why would the kernel drop packets?

I interrupted tcpdump with Ctrl+C and got this total summary: 579204 packets captured 579346 packets received by filter 142 packets dropped by kernel What are the "packets dropped by kernel"? Why ...
1
vote
1answer
56 views

Built new kernel, LVM won't mount from initrd

I need to upgrade my kernel on a RHEL 5 system to build with some experimental drivers. I have configured the kernel with module loading for LVM (dm_* modules). Once the initrd runs the /init ...
3
votes
0answers
64 views

Output shutdown messages to multiple consoles

I have configured my system to direct console output on boot to serial and vga using kernel parameters. Serial is the last argument in the kernel parameters and will be the default used for ...
0
votes
0answers
145 views

psmouse sync issues!

I have Compaq CQ61-420US (64-bit AMD) laptop with Synaptics touchpad checked using $ egrep -i 'synap' /proc/bus/input/devices N: Name="SynPS/2 Synaptics TouchPad" But recently after Arch Linux ...
3
votes
1answer
53 views

Is there a man section or other doc repository for data structure definitions?

For the millionth time or so I had to look in /usr/include/foo.h to find the members of a struct foo or foo_t or whatever. There's a man section for library and kernel calls, some of which include ...
0
votes
0answers
53 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 ...
5
votes
1answer
93 views

Linux kernel dropping custom keyboard scan codes

I have a vintage IBM 122 key model M keyboard that I am adapting for use on a modern computer. I am using a Teensy 2.0 to do the encoding and to handle the USB side of things. I borrowed the firmware ...
0
votes
1answer
100 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
votes
0answers
47 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 ...
2
votes
3answers
60 views

Un-mount active partition

Is it possible to umount the partition, whose files/directories are in use? The underlying files and directories are in memory so un-mounting the partition is technically safe (I guess). But umount ...
1
vote
0answers
77 views

cross compile embedded arm

I have the android 4.2.2 code in directory /home/sghPhone2 which compiles normal with make menuconfig but I need to compile a 4.4 kernel and possibly patch it but when I download the source from ...