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

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Linux kernel 2.6.38 compilation error

When I try to compile the Linux 2.6.38 kernel on my Linux PC, I get: $ make defconfig $ make I get: ubuntu/ndiswrapper/iw_ndis.c:1966:2: error: unknown field ‘num_private’ specified in initializer ...
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How to capture from instensive pro in Ubuntu, Fedora, CentOS using HDMI interface?

I am trying to use PCI-X1 capture card (intensiy pro) using Ubuntu 10.04 (now) / 11.04 (failed) or Fedora (failed). None of them is yet capturing. I did my best but now i need some backup on this. ...
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What is a “watchdog reset”?

After reading this question, I was a little confused; it sounds like some daemon reacting by rebooting a system. Is that right? Is it a common occurrence in embedded *nixes?
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How do I cause a watchdog reset of my embedded Linux device

Is there a command like vi > out vi | out That I could use to cause a watchdog reset of my embedded linux device?
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Unable to boot custom kernel

I am using ubuntu 11.04 I have a custom 2.6.36.4 kernel source (say in linux_src) Did make mrproper Copied my current configuration from /boot to linux_src/.config Did a make menuconfig, instructed ...
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Using syslog from a kernel module

I am writing a linux kernel module to report statistics and send some log messages. Can I use syslog to accomplish this job? Or is printk the only way?
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How can I reconfigure my Ubuntu PC's 2.6.37.6 kernel to shrink it to 950 KB or less?

I need to recompile the kernel with minimum configuration so that after compiling its size stay below 950 KB and it should boot correctly after compilation. I need to compile with minimum possible ...
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810 views

Grubby fatal error in Linux kernel installation

I have compiled Linux kernel 2.6.24.6 from source (without problem) and tried to install it. Specifically, after unpacking the Linux source code, I did make && make modules to compile. ...
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374 views

Is there a different linux kernel for different architectures?

If I want to build a custom kernel for an ARM architecture, do I need to : a) Download the kernel from kernel.org, make changes to the kernel, build it using some cross compiler (like code sourcery ...
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376 views

UDP multicasting broken after kernel update

I've got an embedded system which is running a stripped down Gentoo userland with a manually build kernel. The system acquires data from a PCI card and sends it out to an UDP multicast group. All ...
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169 views

Does linux have Blackbox like mechanism when system crashed in embeded linux?

In embeded linux, some times after the system crashes, we hope there is a blackbox (will record the key info before the system restart) , in linux, is there have such kind of mechanism to record the ...
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Is there any method to mount a block of memory as a filesystem in linux?

I have a question,in linux, is there any method to mount a block of memory as a filesystem? For example, in X86 architecture, when power on, I reserve a block of memory about 8 Mbytes, and then when ...
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Command to install linux headers fails

I need to install my linux headers for an Nvidia driver install. But I get an error when doing so: peter@peter-deb:~$ sudo apt-get install linux-headers-$(uname -r) Reading package lists... Done ...
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Non-interactive configuration of linux kernel

Is there any method to configure linux kernel in such way (just an example): make config CONFIG_OPTION=y && make config CONFIG_OPTION1=no CONFIG_OPTION3=64 CONFIG_OPTION4=/path/ and all the ...
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218 views

rpm content compress

My default kernel rpm has 12mb size, for some reasons I compile a custom kernel and make rpm from that(make rpm command). However, my custom kernel rpm size is 96mb. I look inside default rpm, in ...
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534 views

How to use a custom crypto algorithm in ipsec?

I wrote a custom algorithm using the kernel crypto API (by modifying the existing SHA1 and DES algorithms), compiled and added the .KO object to kernel. How can I use my algorithm in ipsec and other ...
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Buffer size for capturing packets in kernel space?

Going through the man page of tcpdump, it seems kernel can drop the packets if the buffer is full. I was wondering if: that size is configurable and/or where can I see the size for my distro? From ...
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How to include local header files in linux kernel module

Say I have a module mymod with source files as follows: src/mod/mymod.c src/inc/mymod.h I try to include mymod.h as follows #include <mymod.h> My makefile contains EXTRA_CFLAGS= -I$(...
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ACPI problem with recent kernels

In recent versions of popular Linux distributions (Ubuntu, Fedora, Mint, Debian) I always have to put acpi=off into the kernel parameter list before I want to boot the computer. This happens to both ...
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How to configure CONFIG_DEFAULT_RELATIME to disable relatime

Since linux 2.6.30, filesystems are mounted with "relatime" by default. In this discussion, Ingo Molnar says he has added the CONFIG_DEFAULT_RELATIME kernel option, which: makes 'norelatime' the ...
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Cleancache vs zram?

I have an old laptop here with only 512 MB of RAM. Since a few kernel releases, I am using zram to convert 256 MB of it to a compressed ramdisk which is then used as swap. This has proved to be very ...
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When was `relatime` made the default?

What is the first Linux kernel release to set relatime as the default mount option?
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Why do I get this error installing virtualbox-4.1 on Arch?

I'm trying to install Virtualbox 4.1 from the .run file since Pacman had the 4.0 version only. But when I try installing the file using sh filelocation/filename.run, it gives me the following error- ...
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Is there a vanilla kernel configuration?

A question on Ask Ubuntu asks if there's a vanilla kernel for Ubuntu. Its answer is there is a "Mainline" series of kernels for Ubuntu that use vanilla files with Ubuntu configurations. But how ...
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Fedora 15 address collision on Compaq CQ41?

I keep getting an address collision warning at boot time, between ACPI and Video Rom. If I add acpi=off to grub.conf the error goes away, but then I have no power management (battery icon, proper ...
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312 views

Where to find this specific source (centos 2.6.18-53.el5PAE)

okay all my looking around on the normal kernel site ftp can't find it. I need specifically, the PAE version. I am compiling virtualbox and if you don't use the right source you get this lovely: ...
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Linux source, where are sys_umount and sys_mount system calls? [duplicate]

Possible Duplicate: Understanding the linux kernel source I am sure that I must be missing something, here. I cannot for the life of me find the source code for these system calls. I can ...
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What is new in Kernel 3.0?

I understand this is somewhat less Ubuntu related, but it affects it. So,what is so new about it that Linus decided to name it 3.0? I'm not trying to get information about the drivers that got into ...
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can i modify an .rpm-based system to use .deb files, apt-get and debian/ubuntu repositories?

I recently ran into trouble when installing Debian on a netbook. There were three major hardware/kernel issues that I didn't feel like fixing, and since every single forum/wiki writeup reported the ...
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Silent booting Linux from u-boot

For security reasons I have to boot Linux from u-boot with all output hidden (silently) until a password is entered. I've configured uBoot to do this correctly using the CONFIG_AUTOBOOT_KEYED macro ...
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Make kernel detect garmin device

I'm trying to connect a usb garmin forerunner device to my system, but the usb device is not detected. I have loaded the following mods: garmin_gps 11544 0 usbserial 25449 ...
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What does 'Invalid module format' mean?

After executing... sudo modprobe rt3572sta I get... Invalid module format What does it mean? I'm trying to get Wusb600n v2 working on Lucid Lynx. Does it mean that kernel versions aren't ...
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Linux Kernel logical address space organisation

According to "Write Great Code" in almost all OS run time memory is organized into following regions: OS | Stack | Heap | Text | Static | Storage/BSS [In increasing address fashion] User ...
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Fedora 15 i686 report only 2.6 GB RAM

I have laptop Asus N53SV with 4 GB of RAM, i7 with integrated card and dedicated GPU. My problem on Fedora is that system reports only 2.6 GB RAM. I know that I should use kernel with PAE but even ...
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617 views

Coreboot + QEMU Tutorial Request (Google has failed)

Can anyone point me in the direction of an end-to-end idiot-proof coreboot+qemu tutorial? I'm having trouble understanding how qemu is set up to emulate different hardware (also having trouble ...
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Interruption of system calls when a signal is caught

From reading the man pages on the read() and write() calls it appears that these calls get interrupted by signals regardless of whether they have to block or not. In particular, assume a process ...
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Uname gives unfamiliar timestamp for kernel

I'm recompiling a new kernel (adding some debugging info) on Ubuntu by doing the following: make vmlinux; make install; after this I do a reboot and select my new custom kernel from the list. ...
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RedHat Enterprise Edition Kernel Support

Is there support for Kernel versions 2.4-2.6 in RedHat Enterprise Linux versions 4 and 5?
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How do I know which files will be included in a linux kernel before I build it?

I am working on a project that includes building an old kernel version of linux. This is fine, but I still need to patch the kernel of all previously found security vulnerabilities based on CVEs. I ...
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description of linux kernel boot parameters 'real_root' and 'cdroot'

I am looking for a formal description of the following boot parameters in the linux kernel: real_root cdroot I have problems tuning them to create my own bootable LiveUSB system. Are they ...
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How can I test a kernel module in a mobile device?

I'm writing a module for the Linux kernel. When this module is ready, I'd like it to run in any device running the kernel. How can I test it in an Android phone? Do I need to recompile the whole tree ...
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How to check if CONFIG_HIGH_RES_TIMERS enable?

I have to program a realtime application on Linux, but don't know whether the standard installation of Ubuntu has CONFIG_HIGH_RES_TIMERS enabled. How can I check this? I'm using Ubuntu 11.04 64bit.
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Kernel Mode Setting vs. Framebuffer?

With KMS, the graphics drivers are moved into the kernel. Since the framebuffer was already in the kernel, I wouldn't expect this to affect framebuffer operation. Yet, I read that KMS supercedes the ...
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Config setting for Linux kernel compilation

I need a Linux kernel compiled with debug features for a kernel module development.What all debugging configuration options should I include for kernel compilation,So that I can avail to all available ...
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14k views

Who's consuming my inotify resources?

After a recent upgrade to Fedora 15, I'm finding that a number of tools are failing with errors along the lines of: tail: inotify resources exhausted tail: inotify cannot be used, reverting to ...
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1answer
3k views

What happens the most, context switches or mode switches?

Which happens the most, context switches or mode switches? I have two answers myself, but I do not know which one is correct: Context switches happen in user mode, but this does not mean that a ...
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Preemptive kernel and Physical Address Extension

Is there anyone that can tell me why, on a preemptive kernel, PAE would not work? This question is an exam question, however I haven't got a clue why it would not work.
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What are the Implications of moving to Huge mem kernel on RHEL4

I've been asked to investigate adding extra memory (> 16gb) to a RHEL 4 server and moving to a huge mem kernel. The server is used for Oracle RAC. Is it just a case of installing the hugh mem kernel ...
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NVIDIA installer can't find kernel source/build files (compiled from kernel.org)

I just compiled and installed the new 3.0-rc2 kernel from kernel.org on my Fedora 15 system. Everything seems to work fine and I can successfully boot into the system. However, this broke my ...
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Status of adding Reiser4 to the Linux kernel

I used the Reiser4 fs for some time and would love to see it get into the mainline kernel. I would think the project can still go forward even if Hans is not able to contribute these days. Is there ...