Linux kernel

Discussion about the Linux kernel.

Masive HTB file lots of filters low performance

Submitted by ionut
on December 4, 2009 - 8:25am

#!/bin/bash
#
# HTB Script v0.0.1
#

# Clase
#tc qdisc del dev eth0 root

# 1: root disc
tc qdisc add dev eth0 root handle 1:1 htb default 120 r2q 10
# 1:1 root class
tc class add dev eth0 parent 1: classid 1:0x1 htb rate 950Mbit prio 0

# 1:50 Metro class
tc class add dev eth0 parent 1:0x1 classid 1:0x50 htb rate 800Mbit prio 0

Masive HTB file lots of filters low performance

Submitted by ionut
on December 4, 2009 - 8:11am
Linux

#!/bin/bash
#
# HTB Script v0.0.1
#

# Clase
#tc qdisc del dev eth0 root

# 1: root disc
tc qdisc add dev eth0 root handle 1:1 htb default 120 r2q 10
# 1:1 root class
tc class add dev eth0 parent 1: classid 1:0x1 htb rate 950Mbit prio 0

# 1:50 Metro class
tc class add dev eth0 parent 1:0x1 classid 1:0x50 htb rate 800Mbit prio 0

Association inode - pathname requested by a process

Submitted by Anonymous
on November 20, 2009 - 2:21pm
Linux

Hi all

i want create a LSM function that checks the properties of an inode using as criteria for filtering the pathname requested by a process, not this with symlinks resolved. In what part of the fs code is this information available? There's an existent security hook suitable for this purpose?

Thanks for replies.

Kernel 2.6.27.7-9 for Suse 11.1 help required with CPU Clock freq/speed/ticks

Submitted by subhan222
on November 19, 2009 - 3:57am
Linux

Kernel 2.6.27.7-9 for Suse 11.1 help required with CPU Clock freq/speed/ticks

Problem Statement: High CPU clock speed/freq
Requirement: Obtain a stable CPU clock ticks/speed/freq on Suse 11.1 with kernel 2.6.27.7-9
Questions: Please refer to the bottom of this page

Artifacts in Use:
-----------------------------------
OS:					Suse 11.1

BNX2 trouble (2.6.31)?

Submitted by Anonymous
on November 16, 2009 - 1:29am
Linux

Today got server freezes. In log last message:
Nov 15 23:04:05 !!! kernel: [433562.050053] ------------[ cut here ]------------
Nov 15 23:04:05 !!! kernel: [433562.050070] WARNING: at /build/buildd/linux-2.6.31/net/sched/sch_generic.c:246 dev_watchdog+0x262/0x270()
Nov 15 23:04:05 !!! kernel: [433562.050073] Hardware name: PowerEdge 1950

USB2 Driver Crash after enumeration

Submitted by kerneltrap
on November 6, 2009 - 1:23pm
Linux

Hi,

I am trying to port Synopsys OTG USB driver 2.90. to Xtensa Linux 2.6.29.1.

I got Synopsys OTG USB driver which was for the IPMate platform.

It has the support for the LM_bus and PCI bus. I am not using either

LM bus or PCI for the USB but Xtensa is using Platform bus, So I tried to use the same.

Generic system call interceptor

Submitted by nsa310
on November 3, 2009 - 6:03am
Linux

Hi all !
I am working on writing a generic system call handler, which can intercept (almost) all linux system calls. I have already written a simple module which intercepts chdir() system call. But, the thing is it doesn't sounds like a good idea to write separate function for each system call. So, I am trying to write a generic function which can intercept all the system calls.

premmpt_disable on all cpus

Submitted by Anonymous
on November 2, 2009 - 11:35pm
Linux

my requirement is as follows.

I want disable preemption on all cpus. and then call a function

with on_each_cpu(preempt_disable, NULL, 1, 1); call I dont think it will work.

is there a way to achieve it ?

NFS mount failure

Submitted by Anonymous
on November 2, 2009 - 11:53am
Linux

I have a problem I'm hoping someone can help me with...

I have an NFS server/client setup. On the server side, I export a romfs filesystem to the NFS. The client computers boot via PXE bootloader and mount their root filesystem via NFS, using tempfs/unionfs to make parts of the filesystem read/write (i.e., /etc, /var, etc)

soft lockup and hang

Submitted by gondim
on October 29, 2009 - 3:02pm
Linux

Hi,

I´m looking for this kernel messages. I would like to know how resolve this problem. Please help me. :)
My system is: CentOS 5.4 - kernel version 2.6.18-164.el5PAE
Intel(R) Core(TM)2 Quad CPU Q6600 @ 2.40GHz
eth0: Ethernet controller: Intel Corporation 82566DC-2 Gigabit Network Connection (rev 02)

checking TSC synchronization

Submitted by handrix
on September 14, 2009 - 6:38am
Linux

Im' trying to upgrade a Linux kernel from 2.6.18 to 2.6.30.
The machine is a HP Proliant with Intel Xeon processor double six core. The 2.6.18 kernel work fine.

When booting with the 2.6.30, the kernel can not identify more than 8 CPU and i get this message :

checking TSC synchronization [CPU#0 -> CPU#8]: passed.

And the kernel could not boot.
Please can you help me with this

GDT assignment

Submitted by Anonymous
on September 12, 2009 - 2:22pm
Linux

In older kernels, GDT is set in arch/i386/kernel/head.S. Now, in newer kernels everything moved to arch/x86, bud in arch/x86/kernel/head_32.S i can't find where is GDT set. I mean something like


.quad 0x0000000000000000 /* NULL descriptor */
.quad 0x0000000000000000 /* not used */

Dealing with Linux kernel configuration's diffs

Submitted by Dmitry Shurupov
on September 11, 2009 - 9:22am
Linux

We're using a lot of different kernel configurations on our servers running Gentoo Linux and Linux VServer. Kernels' configs depend on hardware and functions of every server. Every time new kernel is released and/or we need to enable/disable some features for all servers' kernels we have to update .config's manually.

Unix Architecture

Submitted by Anonymous
on September 9, 2009 - 3:28am
Linux

Any one please send the UNIX Architecture which specifies how the UNIX Operating System handles all the System Calls.

ZFS on linux

Submitted by mayurt
on September 9, 2009 - 2:18am
Linux

ZFS support on linux