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

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8
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3answers
7k 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?
7
votes
1answer
6k views

getrusage system call: what is “maximum resident set size”

man getrusage 2 says ru_maxrss (since Linux 2.6.32) This is the maximum resident set size used (in kilobytes). For RUSAGE_CHILDREN, this is the resident set size of the largest ...
3
votes
2answers
5k views

Undefined reference to symbol 'acs_map' when running makeconfig

I get a linker error when I try to configure the Linux kernel with menuconfig: # make menuconfig HOSTLD scripts/kconfig/mconf /usr/local/bin/ld: scripts/kconfig/lxdialog/checklist.o: undefined ...
0
votes
1answer
198 views

I need kernel headers for 2.6.21.5 [closed]

Preferably in slackware module format(lzm). Can't seem to find it. Can anyone help me?
1
vote
1answer
112 views

Removing generic kernel updates from aptitude post custom kernel install

I've updated my Mint 12 system to be running a kernel built from Linus' git repo. Now, whenever I run apt-get upgrade, I see that linux*-generic are still on the update list (they're being "kept back",...
10
votes
1answer
2k views

Why is my initial ramdisk so big?

I'm running Ubuntu 11.10, which came with kernel version 3.0.0-14. I downloaded and built a kernel from the 3.1.0 branch. After installing the new kernel, I see that my /boot/initrd.img-3.1.0 file is ...
2
votes
1answer
373 views

Running a script every time a new kernel is installed

I'm currently having to recompile my wireless driver from source every time I get a new kernel release. Thinking it would be awesomely hackerish to automate this process, I symlinked my Bash build ...
2
votes
1answer
735 views

Compiling a distribution unspecific kernel on two different distributions

I downloaded kernel 3.2.1 from the kernel.org. Compiled it "successfully" on OpenSuse 11.3 64 bit. When I tried to compile the same kernel source on Ubuntu 11.10, I got: ERROR: "...
4
votes
2answers
778 views

Is it normal that a restart is required to mount USB after a kernel upgrade?

Sometimes I see the Linux kernel being mentioned in the list of upgrades, when running pacman -Syu (updating my packages in Arch Linux). Whenever this happens, after installation of the packages, I ...
4
votes
2answers
3k views

Not enough space on / to install new kernel update

During a recent update I received this: Installing: kernel-default-2.6.37.6-0.11.1 [error] Installation of kernel-default-2.6.37.6-0.11.1 failed: (with --nodeps --force) Error: Subprocess failed. ...
5
votes
1answer
13k views

How to get a list of installed external kernel modules?

From the documentation of Linux kernel 3.2 (Documentation/kbuild/modules.txt) === 5. Module Installation Modules which are included in the kernel are installed in the directory: /lib/modules/$(...
1
vote
1answer
2k views

__modver_version_show undefined error during make

Platform: Ubuntu 11.10 64bit Kernel to be compiled: 3.2.1 Error after make: ERROR: "__modver_version_show" [drivers/staging/rts5139/rts5139.ko] undefined! To solve this I copied the .config file of ...
1
vote
2answers
2k views

modprobe: Module ext4 not found. WARNING: no dependencies for kernel module 'ext4' found

I rebooted a compiled kernel 3.1.0, and those are the errors that I am getting: linux-dopx:/usr/src/linux-3.1.0-1.2 # make install sh /usr/src/linux-3.1.0-1.2/arch/x86/boot/install.sh 3.1.0 arch/x86/...
2
votes
2answers
315 views

Precautions to be taken while make oldconfig

If a previous kernel (assuming it is not from the stone age) compiles successfully, does it make sense to assume that old config file if copied to the new kernel, will compile successfully too? What ...
2
votes
2answers
2k views

Updating /boot/grub/menu.lst on OpenSuSe 11.3

I compiled the latest kernel, and the menu.lst is updated as follows. My aim is to keep the other kernel around, so that if the new one fails we can still boot from the other one. Is this the correct ...
6
votes
2answers
16k views

How to create an initrd image on OpenSuSE linux?

/usr/src/linux-3.2.1 # make install scripts/kconfig/conf --silentoldconfig Kconfig sh /usr/src/linux-3.2.1/arch/x86/boot/install.sh 3.2.1-12-desktop arch/x86/boot/bzImage \ System.map "...
5
votes
2answers
2k views

Compiling the kernel with default configurations

Assumptions: The platform: anisha@linux-dopx:~/> uname -a Linux linux-dopx 2.6.34-12-desktop #1 SMP PREEMPT 2010-06-29 02:39:08 +0200 x86_64 x86_64 x86_64 GNU/Linux The kernel downloaded is the ...
3
votes
2answers
4k views

Kernel Panic - Can't find root filesystem / error mounting /dev/root

From here: http://fedoraproject.org/wiki/Common_kernel_problems#Can.27t_find_root_filesystem_.2F_error_mounting_.2Fdev.2Froot A lot of these bugs end up being a broken initrd due to bugs in ...
0
votes
2answers
2k views

critical section for linux

In linux or a library for linux, is there an equivalent to critical section in win32? I am aware of Mutex, but it is not the same as critical section since a critical section uses user-mode spinlock ...
7
votes
1answer
375 views

What do the kernel options in braces mean?

I saw a kernel option today in menuconfig that used braces for its checkbox. {*} Button This isn't listed in the legend at the top of the screen. [*] built-in [ ] excluded <M> module &...
4
votes
2answers
2k views

Multiple root options in Linux command line

My kernel command line looks like this: root=31:0 ro noinitrd console=ttyS0,115200 root=/dev/mtdblock2 rootfstype=squashfs I think the first root entry identifies a disk by its major and minor ...
8
votes
3answers
8k views

How do I tell what version of Gentoo & Linux is running?

Is there a way to tell from Bash what distro version # I'm running and also what Kernel version is included?
3
votes
1answer
850 views

Compiling and installing a kernel.org kernel to a custom volume on disk

I want to compile and install a kernel.org kernel on a custom HDD volume, say /dev/sda5, instead of being merged with my current Ubuntu's directories. I can find information about configuration and ...
4
votes
1answer
2k views

How does the Linux kernel decide how much bandwidth to allocate to Isochronous USB endpoints?

As far as I'm aware, USB endpoints that use isochronous transfers have a 'wMaxPacketSize' parameter associated with them that is used by the kernel to guarantee a certain amount of bandwidth for the ...
8
votes
1answer
16k views

What does the 'i8042.nomux=1' kernel option do during booting of Ubuntu?

I have a laptop with a multi guesture touchpad. My touchpad never works in any Linux distro such as Ubuntu, Fedora, openSUSE, Linux Mint, Knoppix, Puppy, Slitaz and lots more. I have tried lots of ...
2
votes
1answer
920 views

kernel panic error after recompilation

I am completely blocked, but temporarily. I have an Ubuntu 11.10 in good condition, in this one I installed VirtuelBox. I installed on VirtuelBox as Ghest Debian Squeeze with Kernel 2.6.32-5-686. ja '...
4
votes
2answers
1k views

How does X map from kernel key scan codes to a keysym?

According to this page there is no direct mapping from udev key mappings to X, it has its own mappings. X has a (quasi) total independent way of mapping keys: X reads the kernel keycode table at ...
4
votes
1answer
109 views

Is it the process that cleans itself on termination or the kernel?

Recently I found this in a powerpoint presentation: When a program is compiled and linked, the linker inserts some extra code in the program. It is this code that calls the main function about the ...
14
votes
4answers
9k views

How can same fd in different processes point to the same file?

Say I have process 1 and process 2. Both have a file descriptor corresponding to the integer 4. In each process however the file descriptor 4 points to a totally different file in the Open File Table ...
4
votes
1answer
755 views

System call invokation methods in new kernel

I read that in the newer kernels system calls are invoked using the INT X80 instruction and also using the sysenter instruction. And also the sysenter instruction gives faster invocation as compared ...
2
votes
1answer
522 views

Unable to access linux/skbuff.h

I am writing a kernel module where I need to access sk_buff variables. But when I write #include <linux/skbuff.h> Netbeans says it can't locate that header file.
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votes
1answer
1k views

Best method for testing android kernel

I would like to test some of the features of android kernel like inserting a module and collecting certain parameters for research purpose. What would you think the best method for that?
0
votes
1answer
103 views

What's a NM thread?

I am studying OCFS2 kernel source code and I found this comment of function dlm_lanuch_thread in file fs/ocfs2/dlm/dlmthread.c: /* Launch the NM thread for the mounted volume */ So what does the "...
14
votes
5answers
6k views

Any way to restart a Linux machine via SSH if the root filesystem is not working?

Just as a curiosity; something went wrong with a Linux machine, making the root file system show up as "64Z". A few commands work, like top, df, and kill, but others like reboot come up with "command ...
9
votes
3answers
15k 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 state,...
1
vote
1answer
2k views

Is there any X windows system, which is HTML, CSS, Javascript? Such as Web Browser?

For dacades X windows system is either BASH, C or etc. But is there any X windows system or any wrapper which can interpret HTML, CSS, Javascript to general Windows system? I would like to build this:...
4
votes
2answers
2k views

Installing OpenVPN to replace Cisco VPN because Cisco will not work with the kernel I am on or downgrade instead?

I had difficulties installing Cisco5.0 VPN on my Ubuntu 10.04 LTS. I asked for assistance in this question: link to previous question. The answer is that this Cisco program will run on only older ...
1
vote
0answers
504 views

How is the Linux kernel stack organised for ARM architecture?

Can any one explain how exactly linux kernel stack organisation is handled? When a child process is created using the fork() system call, how is the kernel stack space initialized?
3
votes
2answers
736 views

Choosing a device name under /dev from the kernel command line

I am booting CentOS via a USB install. The boot method is simply booting the ISO from GRUB2 installed on the USB Key. The USB key always gets the "name" /dev/sda. Can I change that name from the ...
1
vote
3answers
2k views

How to install kernel on debian with no internet connection

I'm trying to install a newer kernel version on my Debian (squeeze) machine as I need it to get my wireless card working. I have Debian on one partition of my hard drive, Fedora on the other. I'm ...
16
votes
1answer
8k views

What does a kernel source tree contain? Is this related to Linux kernel headers?

In books, I typically read references to the Linux Source Tree at /usr/src/linux with the usual set of subdirectories (arch, block, crypto, ...). I was expecting this tree to contain the binary files ...
5
votes
2answers
11k views

Unable to boot VM: Error 13: Invalid or Unsupported Executable Format

I used VMWare vConverter and everything converted fine, but when I try to boot I get an error: The physical machine boots correctly, so I don't think it is a source machine issue. I am not sure why ...
-1
votes
1answer
471 views

Set Kernel Root to Same Partition as Boot

Running GRUB, I want to set the kernel root parameter to the same partition (or more generically, to a partition on the same device) as the disk with the bootloader. Initially, the install set the ...
7
votes
1answer
599 views

What are the main differences between Unix and Linux kernels today?

I know that many of the same programs run flawlessly on top of both kernels. I know that historically, the two kernels came from different origins. I know philosophically too that they stood for ...
7
votes
1answer
3k views

Will process ids be recycled? What if you reach the maximal id?

Process IDs are strictly increasing, but if your system runs long enough and there is a lot of processes terminating and starting, you could at some point reach the limit of the underlying integral ...
23
votes
1answer
23k views

How to assign USB driver to device

This question is two-fold: First, how do you manually detach a driver from a USB device and attach a different one? For example, I have a device that when connected automatically uses the usb-...
2
votes
1answer
795 views

Kernel can not boot after upgrade on Fedora OS 15

I am using Fedora 15, and want to upgrade to version 16. I followed the official link Upgrading Fedora using yum - FedoraProject to upgrade my OS by the following command: yum update kernel* --...
9
votes
3answers
4k views

Why does initramfs mount the root filesystem read-only

What is the reason for the root filesystem being mounted ro in the initramfs (and in initrd). For example the Gentoo initramfs guide mounts the root filesystem with: mount -o ro /dev/sda1 /mnt/root ...
4
votes
2answers
2k views

Restricting memory area for linux kernel

I am running ltib Linux on P1022RDK (P1022 Core) platform. I have 512 MB = 0x20000000 memory. I want my Linux kernel to use the second half of the board memory (i.e from 256 MB to 512 MB) and want the ...
10
votes
3answers
5k views

Make changes to /sys persistent between boots

I want to make "echo 1 > /sys/kernel/mm/ksm/run" persistent between boots. I know that I can edit /etc/sysctl.conf to make /proc filesystem changes persist, but this doesn't seem to work for /sys. ...