August 2011 - kernelnewbies@kernelnewbies.org

Re: Dev Environment?
by Mulyadi Santosa Aug. 15, 2011

Aug. 15, 2011

Hi :) On Sun, Aug 14, 2011 at 11:51, Daniel Hilst Selli <danielhilst(a)gmail.com> wrote: > Thanks Mulyadi, I was installing gentoo with qemu.. but takes soo long to > install that I give up, > I was thinking in a minimal distro as dsl or lfs. What you suggest ? Next time, pls keep kernelnewbies list address intact :) About disk image, how about using prebuilt one provided in http://wiki.qemu.org/Download? or ones in http://fs.devloop.org.uk/ ? I think busybox might be a good fit for a tiny setup :) -- regards, Mulyadi Santosa Freelance Linux trainer and consultant blog: the-hydra.blogspot.com training: mulyaditraining.blogspot.com

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Re: Dev Environment?
by Mulyadi Santosa Aug. 15, 2011

Aug. 15, 2011

Hi :) On Mon, Aug 15, 2011 at 11:38, Christophe <kereoz(a)kereoz.org> wrote: > I personally like to debootstrap a Debian and make a qcow2 image from it. You don't need the kernel to be on the image as you can directly pass a kernel to qemu with the -kernel option. I agree, just to add that AFAICT the provided qemu image in the links I mentioned has no kernel image inside them -- regards, Mulyadi Santosa Freelance Linux trainer and consultant blog: the-hydra.blogspot.com training: mulyaditraining.blogspot.com

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Tracing file size changes
by Chris Aug. 15, 2011

Aug. 15, 2011

I'm trying to think of a good way to figure out where space is going on somewhat large and busy filesystems. Often I will be notified by nagios that I am running out of space somewhere, and it will even tell me what the trend in usage is. So now I know that I lost a bunch of space recently. There are several things I can do at that point: - Check quota usage. If quotas are working correctly, this can sometimes help when one user is obviously using a ton of space. More often than not, there is nothing obvious, quotas aren't working or the space is used by system accounts that provide no help in knowing where the space went. - Use du. This is just plain painful and time consuming. Doing this usually causes too much load. Without knowing other ways to find information, I was thinking it would be really nice to have a way to see which files or directories grew or shrank since some point in the past. Would it be possible to get the kernel to tell me when files were opened for writing and closed so I could record the size difference? I know there are various file notify mechanisms, but from what I can see, they don't handle millions of files very well. Of course I'm open to other ideas, but this was my curiosity.

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Purpose of using __be16 inside a data structure?
by 陳國成 Aug. 14, 2011

Aug. 14, 2011

Hi all, Please tell me the difference between using unsigned short and __be16 to declear a variable in a data structure. For example, in include/net/inet_sock.h, struct inet_sock is decleared as struct inet_sock { __be16 inet_dport; }; not struct inet_sock { unsigned short inet_dport; }; I think it has something to do with endianness. But I see that both __le16 and __be16 are unsigned short when using gcc with -E option for little-endian and big-endian platform. Can someone give me more information? * little-endian typedef unsigned short __u16; typedef __u16 __le16; typedef __u16 __be16; * big-endian typedef unsigned short __u16; typedef __u16 __le16; typedef __u16 __be16; Regards, GC

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Dev Environment?
by Daniel Hilst Selli Aug. 14, 2011

Aug. 14, 2011

Hey people.. I start to read a book about kernel, and want to make some changes to it, for study purpose. ue I think in edit it, an use qemu to test it with some minimal distribution installation. So how people usually do? Thanks! -- "Do or do not... there is no try" Yoda Master

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Need help in understanding sysfs
by Vaibhav Jain Aug. 12, 2011

Aug. 12, 2011

Hi, I need to undestand sysfs and make changes to it. Please provide me with some good references. Thanks Vaibhav Jain

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Re: about gcc-3.4.6
by esmaeil mirzaee Aug. 12, 2011

Aug. 12, 2011

On Fri, Jul 29, 2011 at 7:46 AM, Pravin Shedage <pravinshedage2008(a)gmail.com > wrote: > Hi Samuel, > > check the FTP link > ftp://ftp.mirrorservice.org/sites/sourceware.org/pub/gcc/releases/ > Actually I have gcc-3.4.6.tar.bz2 for process of installation I did: untar the file ./configure make but I've got error some of the error is: In function ‘open’, inlined from ‘collect_execute’ at ./collect2.c:1537:20: /usr/include/bits/fcntl2.h:51:24: error: call to ‘__open_missing_mode’ declared with attribute error: open with O_CREAT in second argument needs 3 arguments make[1]: *** [collect2.o] Error 1 make[1]: Leaving directory `/home/esmaeil/Documents/software/gcc-3.4.6/gcc' make: *** [all-gcc] Error 2 > > @enjoy.... > > > > On Fri, Jul 29, 2011 at 4:53 PM, Bernd Petrovitsch < > bernd(a)petrovitsch.priv.at> wrote: > >> Hi! >> >> On Fre, 2011-07-29 at 07:14 -0400, esmaeil mirzaee wrote: >> > apologize in advance, I know here is related the kernel but my >> >> Than why do you post here in the first place? >> >> [...] >> > I need gcc-3.4.6 for do work with ubuntu kernel and install some stuff >> > I needed. >> >> You can find the source on http.//gcc.gnu.org/ or - surpise! - via >> Google. >> >> > Again I'm so sorry for interrupt. >> >> No, you are not. >> Bernd >> -- >> Bernd Petrovitsch Email : bernd(a)petrovitsch.priv.at >> LUGA : http://www.luga.at >> >> >> _______________________________________________ >> Kernelnewbies mailing list >> Kernelnewbies(a)kernelnewbies.org >> http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies >> > > > > > > Thanks & Regards, > ---------PraviN--------- > > >

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SYSLOG_ACTION_READ_ALL question
by william douglas Aug. 12, 2011

Aug. 12, 2011

Hello all, I'm trying to figure out why the do_syslog code in kernel/printk.c is using put_user instead of copy_to_user. There is even a comment about how because of sleep, the buffer is read from back to front to minimize the impact of printk overwriting the syslog section we are using. That wouldn't be necessary if a temporary copy was made and then written out with copy_to_user. Does that make sense or am I missing something? Thanks, William

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What's the value of %cs before jump in pm32 on booting?
by jiangtao.jit Aug. 11, 2011

Aug. 11, 2011

Hi all: on booting of x86 top of file arch/x86/boot/pmjump.S there is code ------------------- GLOBAL(protected_mode_jump) movl %edx, %esi xorl %ebx, %ebx movw %cs, %bx shll $4, %ebx addl %ebx, 2f ... ------------------- what's the value of %cs here? how was it loaded? i would really appreciate if someone provide me some references thank you very much 2011-08-11 jiangtao.jit

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Mapped more than Cached in /proc/meminfo
by =/_00/\/\ Aug. 10, 2011

Aug. 10, 2011

Hi, I am trying to analyze memory usage on my system. As first step I am monitoring /proc/meminfo. Surprisingly I see Mapped value is more than Cached. So in which case is it possible to have Mapped more than Cached ? Regards, ~/

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