Questions tagged [linux-kernel]
This tag is for questions about the internals of the Linux kernel itself - particularly about use or configuration of kernel modules or drivers.
487
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Error when compiling Linux kernel
I get an error when trying to compile Linux kernel 3.8.0-32 on Elementary OS Luna, based on Ubuntu. I have a Lenovo S400 notebook, and the command I used is:
sudo make-kpkg --initrd --append-to-...
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0
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Installing VirtualBox in linux via a script with also includes signing kernal modules
I have a linux VM (ubuntu 20.04) with secure boot settings active. Basically I need to install virtualBox and then create multiple VMs via virtual box via script only. No manual intervention should be ...
1
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1
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system clock is not set correctly on startup
i have strange problem with the system clock in my Linux system, TinyCore, kernel 2.6.38 .
dmesg says the following:
rtc_cmos 00:04: setting system clock to 2012-08-08 19:20:00 UTC (since_epoch-...
2
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3
answers
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Kernel Compilation: Force all modules to be baked in
I am building a kernel with OpenWrt for a hardware device. As there will no new pluggable hardware which will be added later, I want to make sure that all kernel modules are built into the kernel. ...
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Kernel panic error in Parrot Security, how do I fix it I tried everything
I can't boot into the new 6.5 kernel.
I am using Parrot Security on my laptop and it recently upgraded from kernel 6.1 to 6.5 but I can't boot into the 6.5 kernel.
When I try update this happens:
...
0
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0
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43
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Pgbouncer: Multiple Instances on same host receiving same TCP connection when using SO_REUSEPORT
I was able to setup two pgbouncer instances for database connection pooling, on a single VM (CentOS 7.0) listening to same port (6432) on two different TCP socket (I believe) using Linux Kernel ...
2
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2
answers
7k
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Fuse file system with “default permission” option
I am new to fuse. I have mounted fuse by the following command.
/home/bin/fusexmp /mnt/fuse -o default_permissions -o allow_other -o nonempty -o hard_remove -d
Now If I login as "test" user and ...
0
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1
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Kernel 4.4.1-1 fails to boot - root volume "does not exist" - 3.10.0.327 and 4.3.3-1 both continue to boot fine
I'm trying to install and boot kernel-ml (currently 4.4.1-1) on RHEL 7.2 following the instructions here: http://linuxg.net/install-kernel-4-x-on-enterprise-linux-7-centos-7-and-rhel-7/
Install works ...
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1
answer
92
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Tell Linux scheduler not to use certain CPU cores at runtime?
I want to absolutely remove certain CPU cores from Linux scheduler.
All I found on the Internet is adding isolcpus to grub with rebooting.
But it there a way to do it at runtime (without reboot)?
34
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3
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Why does the Linux SCSI subsystem drive hardware not obviously related to SCSI?
Without knowledge, I would normally expect SATA, SCSI and USB Mass Storage to be driven by different drivers. In Linux however, the SCSI subsystem drives all of them.
Why does Linux use the SCSI ...
0
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1
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214
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Install specific Linux kernel headers
I'm learning how to write a module, and when I initialize "make", I get
make[1]: *** /lib/modules/6.6.6-060606-generic/build: No such file or directory. Stop.
With this Makefile:
obj-m = ...
1
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1
answer
344
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SSD read/write error on ASUS Vivobook S15 S533 (11th Gen Intel) running Ubuntu 22.04 after update
I have Ubuntu 22.04 upgraded from 20.04 installed in 2020. This machine]1 worked well with kernel 5.15.0-43. After recent update (2023.11.28) it often crashes random with I/O error. While crashing it ...
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How can I delete just one queue in htb?
I would like to delete just one queue in htb when having two. My script would be the following one:
TC=/sbin/tc
IF=wlan0 # Interface
DNLD=1mbit # DOWNLOAD Limit
UPLD=1mbit ...
2
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1
answer
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Not able to install curl-devel package on CentOS 7
I run CentOS 7.3 as production server. I executed following commands in sequence ... But not able to install the curl-devel package.
$ yum clean all
$ yum update
$ yum install curl-devel
Loaded ...
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1
answer
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How do I install the newest Linux kernel (6.5 currently) on Linux Mint (21.2 Victoria currently)
I know how to use Mainline, and can install that kernel, but the headers require a newer libc (>= 2.38) than what’s installed (2.35-0ubuntu3.1), and I need the headers to build two modules (...
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How do I stop rfkill module from hardblocking my wifi, without rfkill command?
I went into my BIOS the other day, didn't change anything, and rebooted. After this, my wifi was hardblocked. I looked online for solutions, and learned of the rfkill command. But I get
rfkill: ...
3
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4
answers
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How to launch vmlinuz-linux from efi shell?
How to start vmlinuz-linux from efi shell ? I jump into the ESP and type vmlinuz-linux (vmlinuz-linux is in the ESP) but it says vmlinuz-linux isn't recognized as an internal or external command, ...
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Remove kernels installed from source from Fedora 34
I have compiled and installed a linux kernel from source, installing it with sudo make install, but the system failed to boot.
How can I remove the kernel installed as such?
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2
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LFS 11.2 on Ubuntu Server 22.04: chroot: failed to run command ‘/usr/bin/env’: No such file or directory
I have been following the LFS 11.2 guide and it has gone smoothly up until the chroot part. Although the symlinks have created properly i.e. relative to the LFS directory, the error is still ...
0
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0
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Configure amount of reserved memory for Linux kernel
I am running Linux on an embedded device with 64MB of physical RAM. Linux prints the following message when it boots:
[ 0.000000] Memory: 58944K/65536K available (3072K
kernel code, 576K rwdata, 832K ...
0
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0
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Using ebtables with hostapd to block outbound access from an IoT network
I have a Raspberry Pi set up to control a number of local IoT devices, and needed them connected to the Internet to set them up initially, but want to prevent them from "phoning home" to a ...
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2
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Fedora 37 VirtualBox Error "vboxdrv kernel module is not loaded" and "Kernel driver not installed (rc=-1908)"
(I already tried things from answers in similar questions to this one)
Fedora Linux 37 (Workstation Edition) x86_64, kernel: 6.0.7-301.fc37.x86_64
I installed VirtualBox with sudo dnf install ...
3
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3
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Booting linux without bootloader
I installed Ubuntu-Server in Oracle Virtual Machine and it failed grub install step. At the end of install it gave me a message:
You need to manually boot linux
/vmlinuz kernel on partition /dev/sda1 ...
0
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0
answers
60
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executing bash script on rotation with iio-sensor-proxy
I have a Tablet-laptop where i want to disable a gnome extension when the screen is rotated.
Auto-rotation works via iio-sensor-proxy.
it would be stupid to poll monitor-sensor constantly for resource ...
0
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1
answer
617
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How to install specific kernel version on ubuntu, which disappeared already from repo `deb http://archive.ubuntu.com/ubuntu/`
My current kernel version is "5.15.0-73-generic". There is some "leading" crypto company, which offers product to strenghten company machines, and our company bought their product ...
3
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0
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770
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5 GHz AP Mode with Atheros QCA6174A chipset on CentOS 8
I am trying to set up an 5 GHz access point on a machine with an Atheros QCA6174A-equipped Wi-Fi card running CentOS 8.
However, all 5 GHz bands are blocked (no-IR flag set) for operation in AP mode (...
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1
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146
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Linux from Scratch: can't connect to home WLAN
I started building LFS to learn more about linux internals. I struggel to configure WLAN and can't even narrow down the problem.
On my laptop I have a dual boot (ubuntu 22 and LFS 11.3) and on ubuntu ...
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3
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How do I disable Linux media polling?
I have a USB floppy drive (for reasons, don't ask). When it's plugged into a modern PC with Debian and udev, something is pinging the drive every couple of seconds --- I believe it's looking to see if ...
0
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1
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Why does it go through netfilter postrouting when visiting local ports?
Environment:
[root@VM-32-4-centos ~]# uname -r
3.10.0-514.26.2.el7.x86_64
I have set log printing in the following chain:
[root@VM-32-4-centos ~]# iptables -A INPUT -p tcp --dport 8000 -j LOG --log-...
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Can't login to Ubuntu in virtual machine
When I updated the system, and then I restarted the machine, I don't know why it's showing this picture:
Can someone solve this problem?
I tried to restart the machine again and again, but its still ...
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1
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486
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Linux Kernel Compilation: Debug info generated albeit disabling `DEBUG_INFO`
I regularly compile Linux kernel on my own. For speed issues, I would like to omit debug information.
A minimal way that reproduces the problem is
make localmodconfig
scripts/config --disable ...
0
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0
answers
391
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Not turning off completely the system. its going to the halt mode in Fedora
some time when i want to shutdown the system in fedora, the system not shutdown completely.
in this problem screen is off but fan is working
Not sure if this is relevant,but there are several errors ...
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0
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283
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net.core.netdev_max_backlog - what's the impact when set too HIGH?
I'm working on optimizing and right-sizing my EC2 syslog-ng servers and have some carryover settings in our ansible playbook for kernel settings that were used on "in-house" data center ...
0
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1
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783
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Fedora 37 Infinite boot on kernel 6.1.9-200 (and higher)
Fedora Linux 37 (Workstation Edition) x86_64
GNOME 43.2
Kernel: 6.1.7-200.fc37.x86_64
After selecting kernel 6.1.9 while boot (which is chosen by default) I'm having infinite black screen with ...
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1
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643
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Disable autoremove of old kernel versions on Fedora 37
Somewhy i can't boot on kernel version higher than 6.0.7-301 (more here).
Recently Fedora automatically downloaded kernel 6.1.10, and after a few days 6.1.11. Both of them, as i said, i can't use for ...
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1
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Cannot upgrade linux kernel due to space, but cannot remove older ones
uname -r
5.15.0-60-generic
My apt upgrade is failing with:
Reading package lists... Done
Building dependency tree
Reading state information... Done
Calculating upgrade... Done
Get more ...
1
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0
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224
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Second nvme missing in /dev/ after kernel upgrade
I have been pushing back my kernel upgrades on my arch machine because after upgrading from 5.14.9 my secondary nvme is not populated into /dev/ anymore.
But I want to tackles this now, hopefully with ...
0
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0
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Can we ditch the Linux initial ramdisk if we don't use loadable modules?
I'd like to boot an embedded machine without using a ramdisk image. I understand one of the reasons for the ramdisk is so it can load the filesystem module needed for accessing the root partition (to ...
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What is the exact difference between the parameters (pgpgin, pswpin) and (pswpout, pgpgout) in /proc/vmstat?
Please note that this question is specific to linux only. And by swap space, I mean the dedicated swap partition.
I did google a bit on this, and found these definitions:
Paging refers to writing ...
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0
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How can I install Kernel 5.17 on CentOS 7?
On a CentOS 7.9 installation I have some troubles running newer CPUs, e.g Ryzen 5 5600G (with included graphics).
I concluded that it is the Kernel because it boots with certain versions, with kernel ...
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1
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Kernel panic when trying to setup rootfs over NFS on ARM board
I have a ARM board on which I am trying to configure NFS so that the rootfs will be mounted over a network. How can I resolve this?
My server configuration:
OS: Scientific Linux 6.0
My NFS shares:
...
1
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1
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How to use dracut in chroot environment established through SLES15 Rescue boot image?
To fix an unbootable SLES15 system, I booted the Rescue image, mounted the existing system to /mnt, and then did chroot /mnt (I'm leaving out the details, as those are probably known (or found in How ...
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1
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Defragment BTRFS to change the compression level
I can do:
btrfs filesystem defragment -rvf -czstd ./
But not:
btrfs filesystem defragment -rvf -czstd:1 ./
I get the error:
ERROR: unknown compression type zstd:1
Is there any way to change the ...
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1
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How to switch off discrete graphics card?
I've got one big problem that I simply can't solve. I got a HP Pavilion dv6 Laptop and it runs Linux Mint Debian Edition. This Laptop runs a hybrid graphics system and I want to switch off the ...
2
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1
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Is there anything preventing modifying linux's tcp stack to have over 65,535 ports?
I was reading this and started to wonder of there was anything preventing me from just modifying a copy of the linux tcp stack to support more than a 16-bit header to allow for more ports. Would this ...
3
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1
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High System CPU usage on Linux
We have an unusual problem where some of our Linux servers are going into a state where the CPU utilisation is very high and when we dig down, most of it is in kernel space. The %sys utilisation is 80%...
2
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1
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442
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linux-firmware apt package VS fwupd tool: Are they doing same thing?
I noticed here two things about firmware:
1. apt list linux-firmware
https://launchpad.net/ubuntu/+source/linux-firmware
$ apt list linux-firmware -a
Listing... Done
linux-firmware/focal-updates,focal-...
0
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1
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3k
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Change default kernel for an AWS instance running Ubuntu 18.04
1. Problem summary
I have an instance on AWS running Ubuntu 18.04. The kernel version is 5.4.0. I have installed kernel 4.15.0 but I am failing to set it as the default.
2. What I have tried
A) I set ...
0
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1
answer
135
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Can't open pseudoterminals from local following an update on Arch
I did a complete update (via yay->pacman), restarted, and now I seemingly can't open any pseudoterminals. All I can do is switch to TTY/teletype terminals. If I try to open a terminal app, it just ...
1
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0
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683
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Fedora 35: Switch back to stock kernel?
A few months ago I built a new machine and installed Fedora on it. At the time, 5.15 was the latest "stock" kernel, but I needed some of the Alder Lake fixes/improvements from 5.16 and 5.17,...