how to debug oom killer errors

Hi, How to decode the stats thrown by the oom killer ? Is there any good in depth documentation out there for this ? Node 0 DMA per-cpu: cpu 0 hot: high 0, batch 1 used:0 cpu 0 cold: high 0, batch 1 used:0 Node 0 DMA32 per-cpu: cpu 0 hot: high 186, batch 31 used:25 cpu 0 cold: high 62, batch 15

Re: how do i read a block

Hi, On Mon, May 13, 2013 at 9:52 PM, Matthias Brugger matthias@gmail.com wrote: El 13/05/2013 10:07, shampavman shampavman...@gmail.com va escriure: Hi all, Supposing i create a file of size 10K, it will occupy 2 blocks (4K each). Now if i want to read only 1 block from it how can i

block level cow operation

Hi, I am trying to implement copy on write operation by reading the original disk block and writing it to some other location and then allowing the write to pass though (block the write operation till the read completes) I tried using submit_bio() / sb_bread() to read the block and using the

Can a bio have more sectors than a file system block size

Hi, In the make_request callback function is it possible for a bio to have bio_sectors() count more than the number of sectors in a file system block ? eg : If the disk sector size is 512 bytes and file system block size is 4096 bytes, I have only noticed bio_sectors() to be 8. Never seen

Create a folder in /dev using device_create() (solved)

Hi, After searching a lot figured out that to create a folder under /dev is to use a '!' as separator instead of '/' in the fmt argument of the device_create() call. This works with kernel 2.6.18 onwards. test!power = /dev/test/power Regards. ___

Re: File system development question

Hi, On Mon, Jan 21, 2013 at 4:53 PM, Racz Zoltan racz.z...@gmail.com wrote: Hi. Some days ago I started studying the linux VFS api, and until now I wrote a mountable only file system. I would like to go further than that, but I didn`t find any good documentations on google. Try older

bitops or mutex

Hi, There is a bitmap that needs to be locked across many threads for test / set bit operations. Which one is faster - bitops or mutex ? 1. Bitops : set_bit(5, (long unsigned *)tmp); 2. Mutex : mutex_lock(m); *tmp = (*tmp) | (1 5); mutex_unlock(m); Regards.

Re: Bad magic number and

Hi, On Fri, Dec 28, 2012 at 10:57 AM, Manish Katiyar mkati...@gmail.com wrote: On Thu, Dec 27, 2012 at 8:29 PM, sham pavman shampavman...@gmail.com wrote: I've tried that as well.. and the result is the same. I've little idea on how to start debugging. If you can provide some info it

Re: Bad magic number and

Hi, On Fri, Dec 28, 2012 at 11:35 AM, sham pavman shampavman...@gmail.com wrote: Here is the output # dumpe2fs -h /dev/sdb dumpe2fs 1.42 (29-Nov-2011) dumpe2fs: Bad magic number in super-block while trying to open /dev/sdb Couldn't find valid filesystem superblock. Try $partprobe $fdisk

Re: Need to Add Documents in Linux kernel

On Wed, Dec 26, 2012 at 8:57 PM, Javed Iqbal javedd.iq...@gmail.com wrote: Hi, I just want to know that can I add documents in linux kernel version 3.x.x.?? If yes then please tell me the procedure to add the documents? 'Documentation' folder inside the kernel source tree.

Re: writes to unmounted partitions

Hi, IIRC, blktrace is designed to monitor such I/O events at the block level. Try it :) Ok I will try that. I was thinking about it and something that made it clear to me is : Since its writing to the actual disk through /dev/sdaX the kernel knows about it, since its the one that is

writes to unmounted partitions

Hi, I am confused on how does Linux kernel handle writes done directly to the /dev/sda3 partitions which is not even mounted. Is the kernel even aware of such writes, does it go though the request queue, I/O scheduler, etc ? Is it possible to monitor such writes ? Regards.

Re: writes to unmounted partitions

Hi Asutosh, It does a raw read and write. The I/O operations go through request queue and I/O scheduler but not through any file-system. The writes and reads would start from the offset that is provided in the read and write call. Is it possible to monitor such writes ? Please explain what

Re: request memory from kernel

Hi, On Sat, Nov 3, 2012 at 9:41 PM, Mulyadi Santosa mulyadi.sant...@gmail.com wrote: Hi.. Someone is kind enough to summarize how to use memory pool here: http://venkateshpnv.blogspot.com/2011/05/memory-allocation-rough-notes-by-chaitu.html What do you think about using vmalloc() ?

first block in ext3 filesystem

Hi, I came across this $sudo dumpe2fs /dev/sda1 4KB Block Size Group 0: (Blocks 0-32767) Primary superblock at 0, Group descriptors at 1-1 1KB Block Size Group 0: (Blocks 1-8192) Primary superblock at 1, Group descriptors at 2-2 Why does first block start from 0 in the 4KB block size

Re: first block in ext3 filesystem

Hi, On Mon, Aug 6, 2012 at 11:49 PM, Manish Katiyar mkati...@gmail.com wrote: Let's say superblock is always written at a fixed offset of 1024 (they have to because e2fsck has to find it) in the filesystem. What would be the block numbers with block sizes 1k and 4k ? I was confused about

Re: Suggest good reads..!!!

Hi, On Wed, Jun 6, 2012 at 11:08 PM, Ezequiel Garcia elezegar...@gmail.com wrote: Hi, For kernel programming the books already mentioned are excellent for starters. Solaris Internals - 2nd Edition Regards. ___ Kernelnewbies mailing list

Re: Doubt in CDROM Ejecting Program

Hi, On Sat, Nov 26, 2011 at 10:33 PM, Niamathullah sharief newbie...@gmail.com wrote: I am having code for ejecting CDROM in my Linux system. This is code CDROM is ejecting fine. ie its opening. But i don't know how to make my CDROM to close. Even if i run these program again its not closing.

Re: Kernel not showing in grub2

Hi, On Wed, Sep 28, 2011 at 6:41 AM, scott redhowlingwol...@nc.rr.com wrote: I compiled a 3.0.0-rc7 kernel. Everything went smoothly except it doesn't show in the grub menu even after doing sudo update-grub. I see the kernel in /boot/grub/grub.cfg. Everything appears right with the UUID's and

Re: How to make the kernel support NTFS?

Hi, On Tue, Aug 23, 2011 at 9:28 PM, Parmenides mobile.parmeni...@gmail.com wrote: Hi,    I have dumped a lfs 6.3 cdrom to a virutal hard disk in vmware, and it goes without any problem. The original kernel version of lfs 6.3 is 2.6.25. I have upgraded it to 2.6.34 and it seems work well.

Re: [ Kernel not booting up ]

Hi Ashish, On Sun, Aug 21, 2011 at 7:24 PM, Kaustubh Ashtekar ksashte...@gmail.com wrote: On Saturday, August 20, 2011, ashish raste rasteash...@gmail.com wrote: Hi all, Recently I compiled and tried installing kernel (2.6.39.3), which I downloaded from kernel.org All the activity that I

Re: MSI-edge in /proc/interrupts

Hi, On Mon, Aug 8, 2011 at 12:47 PM, J.Hwan Kim frog1...@gmail.com wrote: Hi, everyone When I read /proc/interrupts, it displays interrupt type of my ethernet card with MSI-edge. Does it mean MSI-X interrupt or MSI interrupt? I set to my ethernet driver operates with MSI-X interrupt.

failed to do make menuconfig

Hi, In the latest staging tree I cant do make menuconfig or even make config prashant@mint11 ~/linux-2.6 $ make menuconfig HOSTCC scripts/kconfig/mconf.o HOSTCC scripts/kconfig/zconf.tab.o In file included from scripts/kconfig/zconf.tab.c:90:0: scripts/kconfig/lkc.h:27:22: fatal error:

Re: LinuxCon Japan Videos

On Sat, Jul 16, 2011 at 1:56 AM, Paul Fisher r01@gmail.com wrote: Can anybody point me at this year's LinuxCon Japan video recordings? Are they available somewhere? http://video.linux.com/video/2082 ___ Kernelnewbies mailing list

Re: Questions regarding console drivers..

Hi sandeep, On Wed, Jul 13, 2011 at 4:47 PM, sandeep kumar coolsandyfor...@gmail.com wrote: Hi all, 4) How to know how many number of consoles are running at a time? /sys/class/vtconsole/ http://www.linux.it/~rubini/docs/sercons/sercons.html ___

Re: how to apply patches from git ?

Hi Ravi, On Thu, Jul 14, 2011 at 2:23 PM, RKK kulkarni.ra...@gmail.com wrote: Hi Prashant, On Thu, Jul 14, 2011 at 1:46 PM, Prashant Shah pshah.mum...@gmail.com wrote: Hi Ravi, If its a public mailing list then I use a newsgroup reader that will allow me to download the entire patch email

Re: how to apply patches from git ?

Hi, On Thu, Jul 14, 2011 at 3:13 PM, RKK kulkarni.ra...@gmail.com wrote: Hi Prashant ,  thanks for that i have set up the pan news reader. i tried applying patch but it dint work. guess have to check git apply for that. yes. git apply will work. also, how do u clone a particular git tree

question about staging tree branches

Hi, There are 4 branches in the staging tree remotes/staging/master remotes/staging/ralink remotes/staging/staging-linus remotes/staging/staging-next Is the staging-linus is what Linus merges and staging-next is merged by linux-next tree ? What is ra-link for ? Regards.

Re: timer problem

Hi, On Thu, Jul 7, 2011 at 2:48 PM, Daniel Baluta daniel.bal...@gmail.com wrote: On Wed, Jul 6, 2011 at 11:48 PM, Daniel Baluta daniel.bal...@gmail.com wrote: Hello Prashant, is the one pointed below (schedule_timeout called in interrupt context). Yes indeed ! the call to in_interrupt()

Re: Problem in compiling a kernel module

Hi, On Sun, Jul 10, 2011 at 11:36 AM, Ponkumaran Annadurai aspkuma...@gmail.com wrote: when I tried your script it prompted that there might be tab instead of eight spaces. So I inserted 8 spaces there, but it still prompted the same. Email is messing up with spaces/tabs. Remove all spaces/etc

Re: Problem in compiling a kernel module

Hi, On Sun, Jul 10, 2011 at 11:36 AM, Ponkumaran Annadurai aspkuma...@gmail.com wrote: when I tried your script it prompted that there might be tab instead of eight spaces. So I inserted 8 spaces there, but it still prompted the same. Sending file as attachment. Makefile Description:

Re: Problem in compiling a kernel module

Hi, On Sun, Jul 10, 2011 at 11:36 AM, Ponkumaran Annadurai aspkuma...@gmail.com wrote: Also I couldn't understand the script (particularly $(MAKE) - what does the variable stands for? also the rest of the code after depend.depend.dep). If you can explain the script, I shall know how to edit

Re: Problem in compiling a kernel module

Hi, On Sun, Jul 10, 2011 at 10:07 AM, Ponkumaran Annadurai aspkuma...@gmail.com wrote:  I am trying to compile a sample hello world module, but when issue make command, it says that make: Nothing to be done for `all'..  Also I tried This is the sample Makefile that I use : You need to replace

Re: interview question how does application connects to device

Hi, On Wed, Jul 6, 2011 at 9:38 AM, Abhijit Pawar apawar.li...@gmail.com wrote: This is good. One more addition from my side which is not necessarily the answer to Greg's question: Bottom Halves are discouraged now days in driver. then what are the alternatives ? are there any articles or

Re: interview question how does application connects to device

Hi, On Tue, Jul 5, 2011 at 9:45 AM, Bond jamesbond.2...@gmail.com wrote: This is an interview question. My answer was In unix it simply opens the device node as a file and sends/receives data and commands from it. A little more detailed method : Userland read/write to the file - Calls C

Re: Gmail complaining about authenticity of emails sent/received via kernelnewbies

On Wed, Jun 29, 2011 at 6:15 PM, Rik van Riel r...@surriel.com wrote: Did Gmail make changes perhaps? just a wild guess. maybe something related to SPF http://mail.google.com/support/bin/answer.py?hl=enctx=mailanswer=185812 I know that the message was really sent by the sender. What can I

Re: 回复： The problem with the installation of the latest kernel

Hi, On Fri, Jun 17, 2011 at 8:10 PM, david gw...@yahoo.cn wrote: HI: I have tried this command, but it asked me a lot of other new config symbols which I don't know whether to include, exclude or make them modules to the kernel. Just hit enter - it will take the default value.

Re: 3.0.0-rc? kernel suddenly loses sound on my ubuntu 11.10 system

Hi, sound worked just fine (intel hda). i also identically configured and built a newer 3.0.0-rcsomething kernel, but when i boot that newer kernel, i have no sound. in particular, when i go under Try to load the module manually by doing a $sudo modprobe snd_hda_intel

Re: Linux kernel thread model

Hi manish, On Thu, Jun 16, 2011 at 10:09 AM, manish honap manish_honap_...@yahoo.co.in wrote: Hi all Can someone please tell me what is the threading model of linux kernel ? user space thread:kernel thread process - n:1 or m:n or 1:1 Straight from Linux Kernel Development 3rd Edition book...

Re: memory management

Hi, On Fri, Jun 10, 2011 at 5:04 PM, Venkateswarlu P p.venkatesh...@gmail.com wrote: how to understand the memory management code in linux any suggestions google for linux memory management subsystem http://linux-mm.org/ http://www.science.unitn.it/~fiorella/guidelinux/tlk/node24.html

Re: Clarification on memory mapping

Hi, On Wed, Jun 1, 2011 at 12:04 PM, sandeep kumar coolsandyfor...@gmail.com wrote: Hi, ioremap() : 2) ioremap does mapping of a particular i/o device to kernel logical memory address. Please correct me if I am wrong. I think this function will remap the I/O registers location to a memory

Re: OS Books suggestion

2011/6/2 Anuz Pratap Singh Tomar chambilketha...@gmail.com: 2011/6/1 Ezequiel García elezegar...@yahoo.com.ar I am looking for some biblographic material for OS learning (mostly for linux). I've read Linux Device Drivers, and I am interested in these: Robert love Linuk kernel development.

simple question about accessing pci io registers

(Prashant Shah); ___ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies

Re: need help with my first device driver

On Fri, Apr 29, 2011 at 8:51 PM, Greg KH g...@kroah.com wrote: On Fri, Apr 29, 2011 at 03:10:53PM +0530, Prashant Shah wrote: Hi, I am trying to write a comedi (drivers/staging/comedi) based driver for the National Instruments USB 6008 USB based data acquisition card. I want to ask a quick