2
votes
1answer
19 views

Installing a new OpenBSD kernel “safely”: why does `make install` go through these extra hoops?

After building a new OpenBSD kernel, the install target of the kernel Makefile does the following: rm -f /obsd ln /bsd /obsd cp bsd /nbsd mv /nbsd /bsd I understand that the first two lines remove ...
3
votes
1answer
37 views

filesystem that works under qemu and I can mount on my host

I'm using qemu for different kind of tasks, I would like to pick a filesystem that is both qemu-compatible and easy to mount under my host. I already discarded both qcow and qcow2 because apparently ...
1
vote
1answer
66 views

Starting my own application at the startup

I am working on zc702 board having ARM Cortex A 9 processor. I have a binary that I got after cross-compilation for ARM (LED blinking). Now I want that this file should execute as soon as the the ...
54
votes
3answers
3k views

What happens when I run the command cat /proc/cpuinfo?

What happens when I write cat /proc/cpuinfo. Is that a named pipe (or something else) to the OS which reads the CPU info on the fly and generate that text each time I call it?
3
votes
3answers
138 views

Is it mandatory to have a file system and MMU in Linux? [closed]

Suppose I do not need a filesystem and I have only applications where data reloading may not be required - so MMU may be redundant. Can I remove these two items from Linux, and boot the OS ...
1
vote
0answers
1k views

kernel: “echo 0 > /proc/sys/kernel/hung_task_timeout_secs”

I got this errors in syslog. Any idea what does it mean? The system is running on Ubuntu 12.04, kernel: 3.8.0-35-generic #52~precise1 It looks to me like failure when trying to write to disk... ...
0
votes
1answer
121 views

Change the root filesystem on an embedded system

I'm using Buildroot to generate an embedded Linux with a kernel v. 2.6.39, which in the end starts busybox. Everything works fine when building with Initramfs as "rootfs". But Initramfs isn't the best ...
3
votes
2answers
133 views

How to fake a filesystem that cannot be mounted by others

I'm currently working on a project. There's an Ubuntu Linux system installed on a disk, DA, mounting the other disk, DB. What it requires is that DB can be only mounted by DA in order to prevent data ...
15
votes
2answers
422 views

Can I list the filesystems a running kernel can support?

I'm trying to detect what filesystems a kernel can support. Ideally in a little list of their names but I'll take anything you've got. Note that I don't mean the current filesystems in use, just ones ...
1
vote
1answer
321 views

Cannot mount eCryptfs

I tried to install eCryptfs on my server to open an eCryptfs I did on my home computer. I got these errors. $ sudo mount -t ecryptfs /home/(place)/enc/ /home/(place)/enc/ Unable to get the ...
0
votes
2answers
229 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 ...
5
votes
3answers
136 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 ...
6
votes
1answer
2k views

dd: writing '/dev/null': No space left on device

I am reading a 550MB file into /dev/null and I am getting dd: writing '/dev/null': No space left on device I was surprised. I thought /dev/null is a black hole where you can send as much as you ...
1
vote
0answers
147 views

memtester runs faster after couple of runs

I am using this test tool : http://pyropus.ca/software/memtester/ And I noticed that first 3 iterations take 4 hours but 30 iterations take only 12 hours. I was hoping that 30 iterations will take 40 ...
2
votes
0answers
61 views

What are the differences between the current Linux kernel and the Unix SVR4 kernel in terms of device drivers+i/o and virtual files systems?

Yes I realize that Linux supports many more file systems and recognizes more devices than Unix SVR4. I'm interested in what the differences are in the abstraction on top of an actual file system, or ...
1
vote
1answer
867 views

Is Native Language Support (NLS) kernel support still necessary?

Does ext4 / cifs system need kernel NLS support ? I'm not sure if it's being handled by user-space program (decoding / encoding) ?
1
vote
1answer
231 views

Recommendation on filesystem for embedded device - RAM or USB

It's been 4 years since I stopped working on my Linux internet radio box. My Linux box was Ubuntu 6.04 with Ext3 fs. At user-space, everything works perfectly except I occasionally bumped into ...
4
votes
2answers
915 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. ...
7
votes
3answers
2k 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. ...
2
votes
1answer
109 views

Is there any method to mount a block of memory as a filesystem in linux?

I have a question,in linux, is there any method to mount a block of memory as a filesystem? For example, in X86 architecture, when power on, I reserve a block of memory about 8 Mbytes, and then when ...
4
votes
2answers
361 views

How to configure CONFIG_DEFAULT_RELATIME to disable relatime

Since linux 2.6.30, filesystems are mounted with "relatime" by default. In this discussion, Ingo Molnar says he has added the CONFIG_DEFAULT_RELATIME kernel option, which: makes 'norelatime' the ...
7
votes
1answer
1k views

When was `relatime` made the default?

What is the first Linux kernel release to set relatime as the default mount option?
1
vote
2answers
460 views

Status of adding Reiser4 to the Linux kernel

I used the Reiser4 fs for some time and would love to see it get into the mainline kernel. I would think the project can still go forward even if Hans is not able to contribute these days. Is there ...
5
votes
1answer
272 views

Why do I need ntfs-3g when I have already enabled NTFS support in the kernel?

When configuring the kernel I see an option to add read-write support for NTFS. Then when mounting my NTFS partition I still have to install ntfs-3g and pass ntfs-3g as the type. I thought if I add ...
2
votes
2answers
151 views

Why does truncate fail for sizes above 2043G in ext3?

Why does this work: truncate -s 2043G foo ...while this fails: truncate -s 2044G foo Why 2043 gigabytes, of all values?