Questions about Linux kernel and Linux kernel related topics eg. implementation details such as system calls, kernel customization, etc. For Linux user space topics which do not involve kernel details, [linux] or distribution tag are more suitable.
Questions tagged [linux-kernel]
3442 questions
378
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How can I find the implementations of Linux kernel system calls?
I am trying to understand how a function, say mkdir, works by looking at the kernel source. This is an attempt to understand the kernel internals and navigate between various functions. I know mkdir is defined in sys/stat.h. I found the…
Navaneeth K N
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Why isn't Linux embraced as the official GNU kernel?
While I knew for quite some time the existence of Hurd, and its mission as the official GNU Operating System kernel, I was wondering how come Linux is not embraced as the official GNU kernel over the years, seeing as it is in a much better state…
NlightNFotis
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129
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What is a tainted Linux kernel?
Under certain conditions, the Linux kernel may become tainted. For example, loading a proprietary video driver into the kernel taints the kernel. This condition may be visible in system logs, kernel error messages (oops and panics), and through…
bwDraco
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125
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6 answers
Why is the Linux kernel 15+ million lines of code?
What are the contents of this monolithic code base?
I understand processor architecture support, security, and virtualization, but I can't imagine that being more than 600,000 lines or so.
What are the historic & current reason drivers are included…
Jonathan
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124
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3 answers
What does the Windows flag in the Linux logo of kernel 3.11 mean?
I've just installed kernel-3.11.0-1.fc20 for my Fedora 19 installation. During the rebooting progress, I saw the Linux logo with a Windows flag in it, what does it mean?
The Fedora 19 is installed in an ASUS TX300CA notebook, secure boot is off,…
LiuYan 刘研
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117
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6 answers
If Linux is only a kernel, then how were its first versions used (without distribution)?
Linux is only a kernel, and if users want to use it, then they need a complete distribution. That being said, how were the first versions of Linux used when there were no Linux distributions?
noop
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How to list all loadable kernel modules?
I'm looking for a few kernel modules to load i2c-dev and i2c-bcm2708. But the modprobe command returns:
sudo modprobe i2c-dev
modprobe: module i2c-dev not found in modules.dep
How do I list all the available modules in the system? In which…
UserK
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2 answers
How to display the Linux kernel command line parameters given for the current boot?
In the grub.conf configuration file I can specify command line parameters that the kernel will use, i.e.:
kernel /boot/kernel-3-2-1-gentoo root=/dev/sda1 vga=791
After booting a given kernel, is there a way to display the command line parameters…
colemik
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93
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8 answers
Linux: How to find the device driver used for a device?
If my target has one device connected and many drivers for that device loaded, how can I understand what device is using which driver?
Deepu
91
votes
2 answers
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? Last but not least, am I correct that it is the…
Martin
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7 answers
Are threads implemented as processes on Linux?
I'm going through this book, Advanced Linux Programming by Mark Mitchell, Jeffrey Oldham, and Alex Samuel. It's from 2001, so a bit old. But I find it quite good anyhow.
However, I got to a point when it diverges from what my Linux produces in the…
user147505
85
votes
3 answers
What does an idle CPU process do?
Looking at the source of strace I found the use of the clone flag CLONE_IDLETASK which is described there as:
#define CLONE_IDLETASK 0x00001000 /* kernel-only flag */
After looking deeper into it I found that, although that flag is not covered in…
grochmal
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Why would anyone choose not to use the lowlatency kernel?
I can't find any good information on the rt and lowlatency Linux kernels.
I am wondering why anybody would not want to use a lowlatency kernel.
Also, if anyone can tell what the specific differences are, that would be great too.
Startec
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"WannaCry" on Linux systems: How do you protect yourself?
According to a rapid7 article there are some vulnerable Samba versions allowing a remote code execution on Linux systems:
While the WannaCry ransomworm impacted Windows systems and was easily identifiable, with clear remediation steps, the Samba…
GAD3R
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Why is 'bc' required to build the Linux kernel?
The Linux kernel minimal building requirements specifies that the calculator bc is required to build kernel v4.10, the minimal version of the tool being 1.06.95.
What use is made of bc in this context, and why isn't the C language directly used…
Ikaros
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