Linux kernel, Linux general

system call implementation

Submitted by veeraiyan
on May 22, 2009 - 7:49am

Hi

i am trying to implement a system call in linux kernel-2.6.29 but this file was missing /usr/src/linux/include/asm-i386/unistd.h

any idea
plz

crc error when uncompressing linux image

Submitted by rohitkugve
on May 19, 2009 - 2:57pm
Linux

Hi,
I compiled kernel 2.6.29 for ixp425 processor. When I load thy zImage and run on my board (which is an E2Brain module with ixp425 processor, called EB425, manufactured by Kontron), it says

Starting user's image 0 ...

Uncompressing Linux.............................................................

crc error

-- System halted

Scheduling in interrupt Kernel 2.4.19

Submitted by Anonymous
on May 18, 2009 - 6:26am
Linux

Hello,
I'm writing a char device module which should implement a cyclic buffer (with forced overwriting of older data). I want another module (a network device) to write on such cdev, while on the other hand I'd like to access the cdev with read operations from userspace.
On the network device I'm using sys_write (declared as extern) function,which seems the right function to do the job.

reserving memory for PCI device under 4GB in 16GB RAM PAE 32-bit system

Submitted by msz
on May 17, 2009 - 1:04pm
Linux

I am preparing a server for data acquisition from a big CCD camera. It uses PCI controllers which came with some software including a kernel driver module for 32-bit systems. Specs say Fedora 8 (2.6.26 kernel) but I found it working also in Centos 5.3 (2.6.18 PAE kernel). The driver requires that the appropriate amount of RAM is reserved for its use and it seems that it MUST be under 4GB.

kgdb on ARM

Submitted by DEF
on May 17, 2009 - 11:56am
Linux

Anyone got kgdb successfully patched on kernel 2.6.25.7 for ARM (arm-iwmmxt-linux-gnueabi)?

I get the following using 'linux-2.6.15.5-kgdb-2.4.tar.bz2' (couldn't find the exact kernel / patch?):

me@pc:~/sysbuild/linux-2.6.25.7$ sudo patch -p1 < linux-2.6.15.5-kgdb-2.4/core-lite.patch
patching file Documentation/DocBook/Makefile
Hunk #1 FAILED at 10.

MMC card locking

Submitted by tarigo
on May 15, 2009 - 11:54am
Linux

Hello all!
Does anybody know how to detect that MMC card is locked (by write-protection switch)? For example by ioctl or via sysfs?

P.S. I know that I could guess by write operations failure. :)

linux-netdev 82573E jumbo frames

Submitted by Anonymous
on May 15, 2009 - 10:09am
Linux

Hi Netdev,
Does the 82573E support jumbo frames,
I have about 130 Supermicro servers with this ethernet card, and im trying to slightly increase the mtu ie: babyjumbo.
I know that Intel does not support it, but comparing the FreeBsd em-6.9.8 driver to the linux e1000 shows that perhaps it is supported if ASPM is disabled.

if_em.c FreeBsd driver:

case e1000_82573:

Urgent!! Please help.. How to send a singnal to a process group?

Submitted by maneeshmp
on May 15, 2009 - 8:45am
Linux

I have to send a User defined signal {SIGUSR1 or SIGUSR2} to a process group.. possibly process group of the terminal. Can anyone help me? { i heard that send_sig_info or send_sig can be used. But i have no idea how to use it :(]

Problem on assigning register for Current pointer

Submitted by beparas
on May 15, 2009 - 5:15am
Linux

Hi all,
I am working on MPC8313erdb board, PowerPC, having linux-2.6.23.
I wrote simple hello_world module. At the time of compilation kernel generate error: "include/asm/current.h:35: error: invalid register name for ‘current’"

I can't understand the manning of this.

Code of hello_world module is given below

reading On-Chip GPIO from userspace

Submitted by Anonymous
on May 10, 2009 - 5:50pm
Linux

Hi folks,

i am successfully using gpio-keys on a custom AT91RM9200 board to react on On-Chip GPIO input events.
But if the system has just started, there is no way to figure out in which state these GPIO's are.
What i could do is enabling DEBUG_FS-Support and check /sys/kernel/debug/at91_gpio - but it seems a bit ugly to use a debug facility for production use.

How to debug an embedded linux Kernel

Submitted by DEF
on May 9, 2009 - 9:27am
Linux

I have a embedded ARM linux target and a linux host. I require to debug the embedded linux usbcore and usbserial.ko. I have built a debug kernel and debuf usbserial.

Now I have gdbserver on the target and gdb on the host. Using tcp how to I configure both the host and target to debug the usbcore?

Not able to generate race condition...

Submitted by Anonymous
on May 8, 2009 - 12:39am
Linux

Hi,

I am learning linux kernel. I have written a simple program to understand the usage of mutex variable.

Ideally the following program should generate race condition and should produce the different values on i,j,k and l rather than i = j = k = l = 100(LOOPCONSTANT * Number of threads) on usage of mutex. Here shared variables between threads are i,j,k and l.

VFS function hook

Submitted by ricardomcm
on May 7, 2009 - 6:27pm
Linux

hi folks, i'm trying to hook a function of the VFS, in order to hide a file in the filesystem
(actually a directory, containing some sensitive stuff)
i've read some papers that i found on google, even rootkit sources such as adore-ng
however they seem not to work under recent kernels

here is what i'm trying to do:

struct file *f;

disk cache configuration

Submitted by mbmessaoud
on May 5, 2009 - 1:18pm
Linux

Hi

How to configure disk cache in linux kernel

the first parameter arametre that is displayed when this command is exceuted

cat /proc/meminfo |grep Cached
Cached: 250492 kB ( How to change this value?)
SwapCached: 4700 kB

Any comment is welcome

XFRM policy Update event for Inbound Policy

Submitted by Anonymous
on May 5, 2009 - 10:13am
Linux

Hi All,
I am looking for Policy update notifications from the XFRM during the IPSec Re-keying. I look for the "XFRM_MSG_UPDPOLICY" event. The issue I see is that i Only get Policy updates for the Outbound Policies and not for the Inbound. Below is the dump of " ip xfrm monitor"

Updated src 9.1.1.0/24 dst 11.0.0.0/8
dir out priority 2360