Everything about UNIX kernels: development, configuration, compilation, design, etc.
1
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1answer
55 views
Where to start profiling Linux kernel?
What are the standard and conventional ways of profiling the Linux kernel? I know there is perf tool but is there anything else?
1
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1answer
55 views
What information exactly is in the access control bits of a page table?
I'm currently learning for an exam in operating systems. This includes learning some basics about page tables, which lead me to the question Why using hierarchical page tables? which mentions that ...
0
votes
1answer
64 views
Relation between the kernel version and OS version
I am running a Ubuntu of version 12.04.
Can I use a kernel of version of version 2.4 on it?
0
votes
2answers
26 views
Kernel compilation of version 2.4 on a system running 3.2.0
My current kernel version on with my OS running on is 3.2.0.
Can I compile a kernel of version 2.4.0 on it?
Is there any perfect kernel documentation available? (As I see different ways of compiling ...
3
votes
2answers
116 views
kernel module function call
I write a kernel module which has initialize and end function. I want one more function and want to call it from the user space process at any time i want.
Is it applicable ? If so, how ?
I am ...
-1
votes
1answer
146 views
how to install and build “iw” for android 4.1? [closed]
i need to install iw wireless packages on android 4.1 device.
but i don't know how and what is the require version of the packages to install !!
also is it need linux platform to do this or it is ...
2
votes
5answers
93 views
How to know what to enable in the kernel?
I'm a gentoo user. When compiling the kernel there are a lot of options which one may enable depending on one's hardware.
My question is how to know what to enable/disable, I'm aware of the hardware ...
1
vote
0answers
47 views
Pinnacle TV tuner card, readreg error, dvb_register failed, cx8802 probe failed, firmware never loads
I'm trying to make this card work in a touch screen kiosk running Ubuntu 10.04, kernel 2.6.32-45-generic
This card seems to use the s5h1411 chip instead of the s5h1409 the modules are expecting. I've ...
0
votes
2answers
127 views
Writing a Linux file system for NFS
I want to write my own custom file system in Linux. Can I share it over standard NFS without making any changes to the local NFS server? If so what VFS APIs are required to be implemented by my file ...
0
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0answers
86 views
Invoking memory compaction on linux 2.6.35 kernels and beyond
This LWN article about memory compaction indicates that memory compaction can be invoked in the linux kernel by
Writing a node number to /proc/sys/vm/compact_node, causing compaction to happen on ...
1
vote
0answers
52 views
Is there a way to undo VGA adapter modesetting in Linux
I'm looking for a way to reset the graphics adapter to textmode after it has been set to some sort of graphical mode by the kernel on bootup, and possibly used by an X server.
Is there any code to do ...
1
vote
1answer
56 views
How to give an ordinary user privileged access to a particular syscall in FreeBSD?
I want to give an ordinary user the ability to fchown() files arbitrarily (as if they were the superuser) on FreeBSD. Generally speaking, is there a right way to change the privilege-checking of a ...
0
votes
0answers
109 views
pptp differs between 3.7 and 3.8 linux kernel milestone with 3.2.0-4 milestone
Unfortunately, current kernel of debian has problem with my hardware: 3.2.0-4-686-pae , and when i compile one of 3.7.x milestone or 3.8.1 itself , my problem is solved.
But my problem with new ...
2
votes
2answers
155 views
Linux kernel development for multi core architecture
I am working on a project adapting system software like the Linux kernel. I read one paper titled "Experience on Comparison of Operating Systems Scalability on the Multi-core Architecture" that tells ...
0
votes
2answers
91 views
swap partition and its laws
I remember for choice of swap partition, we should use (swap > 2xRAM) at least.Of course it deprecated , because max of computer's ram is very high. kernel support it.
My question: i remember each ...
6
votes
3answers
551 views
How to cause kernel panic with a single command?
Is it possible to cause a kernel panic with a single command line?
What would be the most straightforward such command for a sudoing user and what would it be for a regular user, if any?
Scenarios ...
3
votes
3answers
90 views
Control how linux deletes files
What exactly happens when an application deletes a file?
Is there any way to control this behavior? Basically I want to shred instead of rm in all cases, but of course applications do not make calls ...
1
vote
2answers
213 views
What's technical difference between official virtualbox and VirtualBox-OSE?
What's technical difference between official VirtualBox and VirtualBox-OSE?
My scenario: I'm using Debian sid, it uses a 3.2.0-4 kernel. When you want to download VirtualBox, you have 3 options:
...
0
votes
1answer
73 views
How does kernel swapping / INT 13h interrupts work?
I'm looking for a way to learn about and understand this technique. Here's what I'm talking about:
Slax boots, {does stuff, like copy itself to RAM}, then transitions control to the kernel/file ...
1
vote
1answer
117 views
Skip all new device drivers in `make oldconfig` for Linux kernel
When using make oldconfig I usually look at new options briefly in case there's something important/useful.
However, on an existing system I couldn't care less about new device drivers for some ...
1
vote
1answer
162 views
Kernel headers for VMware tools
I tried to compile VMware tools on my server. I compiled the kernel myself, I didn't use RPM. As VMware tools needs the kernel header files, I executed the following command in my kernel folder ...
0
votes
2answers
127 views
Kernel/grub : how override root parameter inside initrd script
I have an old kernel ( 2.4.37.9 ) and I want to override or substitute the root=XXXXX parameter to send to the kernel inside the initrd script.
I already made some attempt to do that but it seems ...
1
vote
1answer
77 views
Using a custom name for root device in grub
I'm working on old distro ( slackware 8.1 ) using a kernel 2.4.37.9 and I have the following problem.
I want to use a custom name for boot device, say for example /dev/root1, which can replace the ...
5
votes
3answers
248 views
Disadvantages of linux kernel module?
I am trying to understand the disadvantages of using Linux kernel modules. I understand the benefits of using them: the ability to dynamically insert code into a running system without having to ...
0
votes
0answers
23 views
Compatibility between Xenomai version and Linux kernel version
Is there a way to determine what versions of Xenomai are suitable with Linux kernel versions?
0
votes
0answers
104 views
Lowering kernel timer interrupt frequency
When I run my Virtual Machine with Gentoo as guest, I have found that there is considerable overhead coming from tick_periodic function.( this is the function which runs on every timer interrupt).This ...
0
votes
0answers
79 views
Acer C7 Chromebook 3.5.0-24 kernel problems
I get this error trying to update and up in the top right ( I use gnome classic ) there is a largeish - sign that's red and the minus is white
Message : E:The package ...
3
votes
2answers
111 views
If I redirect logs using rsyslog, will dmesg be affected?
I am trying to get some logging in place and am trying to troubleshoot it and this question became relevant.
I use rsyslog config files to redirect some of my logging. (Will use iptables logging ...
0
votes
1answer
48 views
Initrd : Were can I found the code for real-root-dev
I'm trying to customize my initrd on kernel 2.4.
At some point, inside the file linuxrc, I have the opportunity to set my root device setting the /proc/sys/kernel/real-root-dev variable
The example ...
0
votes
0answers
153 views
PC BSD 9.1 not loading after initial install
I just tried to install PC-BSD 9.1 on my Alienware m14x-R3 laptop (with Optimus support), and it refuses to boot. It will come to the bootloader screen, but when I attempt to boot, the actual kernel ...
4
votes
3answers
159 views
How to list all hardware supported by kernel
I want to see all hardware supported by the kernel in use. For example, if I have the 3.8.x.x version of the Linux kernel, how will I know what hardware is supported there. Tools like lspci, lshw, ...
17
votes
3answers
2k views
What is the difference between reboot , init 6 and shutdown -r now?
I just want to know difference between in
reboot
init 6
shutdown -r now
and which is the safest and the best?
1
vote
0answers
415 views
Intel Core i3/i5/i7 Sandy Bridge CPU throttling
Intel Sandy-Bridge family i5 Core CPU, running Linux kernel 3.2 (Debian Squeeze/Wheezy), under heavy computation load, does not react to to cpufreq-set -g powersave (using acpi_cpufreq module). It is ...
2
votes
1answer
66 views
What is the source of truth for currently active tty/pts connections?
I'm looking for a simple way to determine the number of currently logged in users, using only the filesystem and basic bash functions (instead of using binaries).
The uptime binary appears to be ...
1
vote
2answers
73 views
TLB cache flusing when a page is swapped out
I recently heard that Linux simply flushes the TLB cache when the corresponding data in that physical address is swapped out, resulting in underutilization of the TLB. I don't know whether all OSes do ...
3
votes
1answer
273 views
Writing /dev/random to file?
If you ran the following, what would happen?
cat /dev/random > ~/randomFile # don't run
Would it be written until the drive runs out of space, or would the system see a problem with this and ...
0
votes
1answer
26 views
USB_HID is not working
How do I get a usb keyboard to work? I have already selected and compiled the USB HID transport layer and I don't know what else to do.
1
vote
1answer
141 views
How to avoid overflowing the kernel printk ring buffer?
I'm trying to debug a linux driver and a particular piece of code is behaving very strangely. In order to see what's going on I've filled the code with printk statements so I can see exactly what the ...
6
votes
1answer
118 views
Blocking kernel updates with dpkg
I'd like to block all distribution-shipped kernel updates due to a nasty thing that recently happened to me. (I'm on a Ubuntu 12.04 amd64 derivative.)
I'd like to block all updates to installed ...
2
votes
1answer
461 views
Kernel config for ASUS P8Z77-V mainboard series
I want to build a kernel (3.6 series) for a system with a ASUS P8Z77-V mainboard. Which settings fit to the built in components?
(The ideal answer would contain an example .config for this board.)
# ...
2
votes
0answers
38 views
kgdb not returning control to gdb
I've compiled a kernel with kgdb support and I'm trying to debug it. I have two machines running, a debug machine (running the kgdb kernel) and the machine I'm using to debug it. They are connected ...
3
votes
0answers
93 views
My SMDK2416 (for s3c2416) kernel works on 64MRAM but crashed on 128M
I'm currently working on embedded arm linux with smdk2416(s3c2416)
The kernel is working on the 64MRAM. Recently, I need to increase the RAM from 64M to 128MB with 64MB on bank0 and 64MB on bank1.
...
1
vote
1answer
148 views
USB3 Hard Drive Not Recognised by Linux
My external USB 3 hard drive is behaving very strangely:
If I plug it into a USB 2 port, it works fine
If I plug it into a USB 3 port, it doesn't work at all. It's not even mentioned in ...
1
vote
3answers
283 views
How to know <root of the kernel source tree>
In https://github.com/facebook/flashcache/ there is a saying
make KERNEL_TREE=<root of the kernel source tree>
This builds both the flashcache.ko and 3 utilities.
...
2
votes
0answers
159 views
Failed to execute shell script from “network” udev rule to change the MAC-address
I am trying to execute a shell script from udev rule, when a network interface is added, as follows:
SUBSYSTEM=="net", ACTION=="add", KERNEL=="eth*", PROGRAM="/usr/local/bin/changemac.sh", ...
7
votes
1answer
339 views
Why does Red Hat Linux use such an old kernel?
Why does RHEL (and its derivatives) use such an old kernel? It uses 2.6.32-xxx, which seems old to me. How do they support newer hardware with that kernel? As far as I know these kind of distributions ...
1
vote
1answer
136 views
Compile Linux Kernel w/ Dynamically (Un)loadable usbserial Module
I've attempted to install drivers for an FPGA device, but require that I remove the usbserial module. This happens to be impossible because usbserial is a built-in module. It was suggested that I ...
-1
votes
1answer
68 views
Upgrading the kernel in Redhat Linux 6.0
How do you upgrade the kernel in Redhat Linux 6.0?
And how can I confirm whether it is updated or not?
1
vote
1answer
126 views
Removing builtin modules in Linux
I'm currently attempting to remove the usbserial module in order to install a new driver module. When I attempt to remove the module I get the following issue:
[root@localhost xr21v141x-lnx-3.0-pak]# ...
2
votes
0answers
151 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 ...
