The kernel of operating systems popularly known as Linux, or sometimes GNU/Linux.

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DisplayPort and Intel HD cause GPU hangs

My system has problems with the displayport connection. This is indicated by several problems that, at the first glance, do not have anything in common. The reason why I claim DP for beeing the cause, ...
0
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1answer
17 views

How does BeagleBone Black Linux bootstrap change when System 5 init is replaced by systemd? [on hold]

We have BBB based custom Linux board running Linux 3.12. We are current using SysV init for boot. I understand that boot happens in following sequence: ROM code looks for boot device based on boot ...
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21 views

How to Study Effect of zram on Memory Size and Paging?

Situation: to study the effect of zram's virtual memory compression (wiki) on memory's size and its speed Motivation: I experience no effect on the memory's size but increased amount of errors from ...
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0answers
35 views

Are there technical limitations preventing root=UUID=<filesystem-uuid> support? [closed]

There is no code in kernel-source/init/do_mounts.c for mounting a filesystem by its UUID, however there is code for mounting a filesystem by that filesystem's partition's UUID. Are there any ...
5
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1answer
42 views

Does linux stops processing related to GUI when we remove the desktop screen from connection from cabinet(CPU box)?

When there is big non interactive software running and if I required more processing power then, after removing the desktop screen does kernel stops processing related to GUI(graphical user interface) ...
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19 views

How to prevent access to HDD during Live-CD operation?

I want to safely disable the harddrive / harddisc (HDD) of my computer with boot parameters. I can not physically unplug it. BIOS / UEFI does not provide me an option to disable it. Can I use the ...
8
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1answer
149 views

Where in GRUB2 source code is the handover/jump to kernel code?

I'm looking for the line of code where GRUB2 finally jumps to kernel code and thus hands over execution on x86 systems? I guess it's in an assembler file since this is very low architecture stuff. I ...
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9 views

Unknown symbol usb_register_driver and usbderegister when inserting the kernel module without GPL licensing

I am a newbie to linux kernel modules. I have written a simple usb driver. The problem that I am facing is when I try to add module to the kernel I get the error "unknown symbol in module". in "...
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9 views

i want to tranfer a particular image from one screen to another using serial port [closed]

Can I get a Step by Step guidlines .even they are asking use uart port i dont know how to do it cane anyone help me it will be very greatfull
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2answers
26 views

Can initramfs programs access all memory - do they run in real or protected mode?

This is in the context of current 64-bit processors and current linux kernels (I'm using 4.6.4.) Is it possible for me to write a program that during boot can examine base memory, 640k and under, ...
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12 views

How are separate stacks for different threads allocated in kernel mode for a process in Linux Kernel?

If a system call is made for a process and sitting in kernel mode, if 2 threads are created then a)how are the stacks for each thread is created in kernel? b)If one of the thread switch back to ...
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1answer
25 views

How to upgrade kernel with all dependencies in Debian?

I tried to select a newer version in aptitude for linux-image-amd64, but it did not upgrade other packages like linux-headers-amd64 which would likely result in broken system. I must be doing ...
0
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1answer
13 views

why skb buffer cannot be queued on two lists at the same time?

why an skb cannot be queued at 2 list at the same time? I have observed kernel panic while queuing skb at another list even if it is queued in at original list. Let me give an example where even ...
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1answer
463 views

HP SmartArray RAID5 recovery on linux

This is a long time in the making, and I've finally got it working so I thought I'd share this with as many people as I can in case they're in a similar situation. Long story short - HP SmartArray ...
3
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1k views

Kernel does not detect Hardware / Software or Hardware fault

I've got more of a basic question for you: My Linux kernel (I tried several here from stock 2.6, 3.2 and 3.5 as well as a custom 3.7.3 one) does not detect my synaptics touchpad - or I am too dumb ...
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2answers
53 views

Running a program after system startup directly from the linux kernel

I am trying to run my application directly from the linux kernel (without using cron or something similar). I've tried using ./init/init.c, but it runs too early: $ dmesg ... [ 0.605657] TEST!!! ...
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1answer
1k views

Issue with Hugepage reservation in linux

I have reserved hugepages for my process using below commands: #echo 64 > /sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages #mkdir -p /mnt/huge && mount -t hugetlbfs nodev /mnt/huge ....
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132 views

switch_root with systemd: “Too many levels of symbolic links”

I'm trying to boot a proprietary kernel build and OS after an upgrade to libc and numerous other tools. I'm booting using an initramfs in the 3.2.0 kernel with some utilities, like busybox. However, ...
0
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1answer
14 views

Applying RT_PREEMPT

I'm trying to install a kernel with the RT_PREEMPT patch on a Lubuntu 16.04 distro and running into some issues I'm not sure how to deal with. I've downloaded the sources for kernel v4.4.12 (linux-4.4....
3
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1answer
22 views

Is there a definite way to relate a driver's source code in Linux kernel to the device itself?

Linux kernel's source code contains the sources of drivers for plenty of devices under /drivers directory. Sometimes by looking at the source code comment, it's possible to get a hint of the device ...
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12 views

Why are these printfs behaving differently? [migrated]

I'm practicing threaded programing and found this. When I printf("1"), the output will comes after a few seconds, but when I printf("\n"), the output comes step-by-step. Why? #include<stdio.h>//...
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3answers
556 views

Does linux modules/drivers belong to kernal space or user space

Some articles say that modules/drivers belong to kernel space as it take part in forming the kernel; (reference: http://www.freesoftwaremagazine.com/articles/drivers_linux) While others say that ...
3
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2answers
242 views

What is zImage, rootfs

I am very much new to Embedded Linux. We use poky build system. We just use bitbake linux-imx command to build the kernel. It generates some files zImage, rootfs, uboot and also a sdcard image. We ...
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30 views

Which Kali Linux kernel image should be chosen and why? What is the difference?

Among the following, which Linux kernel should be chosen and why? How does each of them differ from vanilla kernel? What is meaning of grsec, bpo, rt and dbg? What kind of functionality do they add ...
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1answer
23 views

After modifing the source code of existing file system (such as ext2), how to rebuild and install it?

I am now learning the source code of ext2. I think the best way to understand it is to play with it, but I never built a Linux kernel before, so I was wondering if somebody could give me some detailed ...
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13 views

How do I access USB endpoints with recent Linux kernels?

I am modifying some dated code (from year 2011; see here) that accesses a USB endpoint in the path: /sys/class/usb_endpoint/usbdevBUS.DEVICE_epENDPOINT/device where "BUS", "DEVICE", and "...
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25 views

Are source IPs included in Linux's Ephemeral Port Uniqueness?

From http://aleccolocco.blogspot.com/2008/11/ephemeral-ports-problem-and-solution.html (2008) Linux shares the assigned list of ephemeral ports across all local IPs for unconnected sockets. ...
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62 views

Make kernel: recipe for target failed

I'm trying to get into linux kernels and I found a nice book which I wanted to read. Starting requirement is a readily built kernel which I'm trying to achieve for a few days now. As of now I'm ...
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2answers
6k views

Understand logging in Linux

As I understand, Linux kernel logs to /proc/kmsg file(mostly hardware-related messages) and /dev/log socket? Anywhere else? Are other applications also able to send messages to /proc/kmsg or /dev/log? ...
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1answer
865 views

APEI Generic Hardware Error : PCIe error with ATTO SAS HBA

Recently we upgraded a remote server to a new Dell PowerEdge T630 with dual CPUs (so all PCIe slots are active). It had been running for several weeks fine before we added an IBM LTO5 tape drive that ...
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1answer
806 views

How to Connect Internet in Zedboard using Linux via SDCard

I am working on Zedboard Zynq 7020. I have booted the Linux via SD card through Zedboard. The linux display can be shown onto the monitor via VGA cable. But I cannot connect that linux to internet. ...
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56 views

kernel address and completely reserve memory block

I want to reserve initial 512M of total 1G RAM (768 MB is mapped as LOW MEM and 128 for vmalloc). The kernel data and text is residing in the initial section of RAM (starting at 0xc0008000). How it ...
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2answers
1k views

Linux/compiler-gcc5.h: No such file or directory

I run into problem compiling a kernel scheduler for testing the compiling error linux-2.6.32-rc3/include/linux/compiler-gcc.h:86:30: fatal error: linux/compiler-gcc5.h: No such file or directory ...
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2answers
99 views

Attempting to compile any kernel yields a certification error

I'm currently attempting to follow this guide in order to install the 4.5.7 kernel with Grsecurity on my Kali Linux desktop. I am following that list of instructions verbatim, except for the fact ...
7
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1answer
4k views

“Northbridge Error (node 0): ECC Error in the Probe Filter directory”

I've received an e-mail from a user worried that the following errors on one of his servers is indicative of a serious problem. The trouble is, the errors below are all that I have to go on. I ...
2
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1answer
3k views

How to fix make error “No rule to make target 'menuconfig'” when building a kernel for Beagleboard?

The aim is to build and install the USB Video Class (UVC) module, via make modules_install. I'm trying to configure the kernel via make menuconfig on Angstrom distribution, running on BeagleBoard-xM. ...
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18 views

Cannot find install-kernel-pkg

I am running Ubuntu 16.04 and am experimenting with building the kernel from source. I am at the step where I want to install the kernel using: new-kernel-pkg --mkinitrd --install --make-default --...
2
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1answer
124 views

CentOS 7 unable to cleanly umount a bind mount using rbind and rslave

The following sequence of commands will fail on CentOS 7 (kernel version: 3.10.0-327.10.1.el7.x86_64): [hidden]$ mkdir -p A B/a C/b [hidden]$ sudo mount --bind A B/a [hidden]$ sudo mount --rbind B C/...
0
votes
1answer
70 views

Trying to get my system running without an initrd

I've been trying to configure a kernel that will not require an initrd to boot. I haven't succeeded. The filesystem I'm attempting to boot from is ext4, and I have all the extended filesystems ...
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32 views

Linux or Unix for Isp providers? [closed]

For an ISP providers without thinking about cost and which one is open source or close source. Consider only performance!!!! which one is better than another?and why?
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1answer
72 views

How do I enable memory zone reclaim mode on the Linux kernel?

I am running Gentoo Linux Hardened using kernel 4.3.3-hardened-r4 on an AMD A4-5300 APU. To troubleshoot a memory problem I have with my system I need to enable sysctl vm.zone_reclaim_mode=1, but ...
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0answers
25 views

3.10 kernel changed how it handles scsi / udev behavior

This is a nfs booted kernel and custom initramfs to execute code on bootup. Here is dmesg after that piece completes and pivots into the running file system. https://paste.fedoraproject.org/387110/...
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2answers
6k views

Error while installing wireless-bcm43142-dkms-6.20.55.19: dependency linux-headers is not satisfiable

I have to install a .deb file with the firmware for the wifi card (This is the name of the file: wireless-bcm43142-dkms-6.20.55.19_amd64.deb; I've downloaded the file from here: http://www.filewatcher....
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How are Linux kernel bugs being tracked?

What an hour of Googling bring out that mainstream Linux kernel bugs are being logged in two distinct systems: Mailing list This is the Linux kernel development discussion and bug reporting ...
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2answers
30k views

What does “INFO: task XXX blocked for more than 120 seconds” exactly mean on Linux?

I had this message in my kernel log : INFO: task XXX blocked for more than 120 seconds. I would like to know what it means technically: under what conditions does the kernel display this message about ...
3
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1answer
5k views

Understanding the difference between pid_max, ulimit -u and thread_max

I am trying to understand the Linux processes. I have confusion on the terms pid_max, ulimit -u and thread_max. What exactly is the difference between these terms? Can someone clarify me the ...
3
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2answers
3k views

How to make EDID

I read the post here and I tried to make do with what I understood from the post but here are some questions: Where is the /lib/firmware located in for example /usr/src/linux/lib/firmware or /usr/...
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30 views

Linux kernel GRUB/boot issue?

I'm working with a specific software package that is only compatible with a older linux kernel version. After installing this older version via the following command $ sudo apt-get install linux-...
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0answers
36 views

How to convert from virtual address to physical address and back? [migrated]

I'm given a task to write an application that will talk to a device. However this is not a driver since device is still being developed and the application is intended to exercises its first revision. ...
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15 views

what does dequeue_task_fair() do in linux scheduler [migrated]

this is a function in linux scheduler, in the implementation of COMPLETELY FAIR SCHEDULER which is in the path: root/kernel/sched/fair.c (link to the file) Now I want to know what does this function ...