January 2011 - kernelnewbies@kernelnewbies.org

[OOT] To all who feel clueless: an advice from another newbie
by Mulyadi Santosa Jan. 6, 2011

Jan. 6, 2011

Hi all (boys and girl, ladies and gentlemen) Lately I realize many member ask quite alike same thing "where do we start? kindly guide me". OK, this is interesting. How do we guide you, if you don't tell us your interest/"expertise"/track record/so on? And more: what's your goal? What do you want to achieve? Glory? Fame? Money? Girls? or just something to fill your spare time? Please realize that there is actually no guide. It's you who has to guide yourself. We can only show you the "way". "Way", ok? road, street, canal, things like that.... but not somekind of food recipe....do this, jump on that, duck at that point. That's guide...but unfortunately we virtually know nothing about you. You, here, are no more than just email address representing a human. It becomes alive when you put your soul in it...your spirit, your desire etc. Then, there's no guide? Actually there is, but not obvious. Look on the way we discuss things, dig archieve...use google etc. Then combine it with your own thinking. Formulate it...I am sure you can do it. After all, if you're so stupid (sorry if it is harsh), you won't come up in this list, right? "Just gave me the tutorial, bro!". OK, that's it. That's the showstopper. We don't accept command. We're not your slaves. Here, everybody partner with others and together we share ideas. That's why it is called community. So if you have bossy mentality, please leave. We won't miss you, not even a bit. We miss friends, but not some clones of Hitler or Mussolini of 21st century. And please, don't make this list as somekind of late soap opera. "I am frustated" "I need that so bad"....so touchy, but that only shows that you're not adult. Instead, you're showing yourself more like 6 months baby who can only cry. World needs tough people. You're not tough? You wanna get some baby sitting? Not here.... last, please don't make this list as somekind of your 911. You dial, you expect answer. No answer, then you think someone violates your human right. Wrong guess. We are people with real life and real life makes "latency". If you plan to see "David Copperfield show", click youtube and enjoy the recording there. We're here to help as much as we can, but we have limitations and we don't dedicate our life just to read e-mails. But if you plan to do such thing, please do so and send us your whole body picture 6 month later, preferrably in 32 bit TIFF format, after making yourself as living answering machine. I risk my neck to be said as complete d**k due to this e-mail. It's ok, at least I try to make this community better :) -- regards, Mulyadi Santosa Freelance Linux trainer and consultant blog: the-hydra.blogspot.com training: mulyaditraining.blogspot.com

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Linux Kernel !!
by Sakshi Malhotra Jan. 5, 2011

Jan. 5, 2011

Hi,Maybe I am not the first one to ask such a question...but couldnt stop myself either...I have read all the relevant books on linux...such as LKD & LDD. I have tried getting some projects on soureforge.net as well ...however, i have not been lucky so far.I want to land up with a job in Linux Kernel but everywhere I get rejected for lack of practical experience.Dont know what to do to get relevant practical experince which gets counted and helps me land up with a job.I am low on morale and confidence...pls suggest.Regards,Sakshi

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addition of guidelines page on kernelnewbies.org
by Anuz Pratap Singh Tomar Jan. 5, 2011

Jan. 5, 2011

With great power comes great responsibility, :p So, I have created the guideline page finally( it took me a while to figure out how to edit wikipages.) I have modified ML page to include link to guidelines page: http://kernelnewbies.org/ML the guideline page is available here: http://kernelnewbies.org/mailinglistguidelines Please let me know if you find any errors/corrections or want to suggest any improvements. Regards Anuz

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Sorry ! I sent the same mail twice
by Sakshi Malhotra Jan. 5, 2011

Jan. 5, 2011

Hi all, I am sorry for sending the same mail twice...actually, the first one didnt show up on the board for a long time.hence, I sent the second one...apologies, once again...Regards,Sakshi

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Doubt regarding __udivdi3
by Gaurav Mahajan Jan. 5, 2011

Jan. 5, 2011

Hi all, I'm trying to insert a module into the kernel (2.6.35.5). There are no errors during the "make" phase. There are only warnings regarding two symbols : WARNING: "__udivdi3" [/media/Study/project_work/splitting_merging/radc_try1/radc1.ko] undefined! WARNING: "__umoddi3" [/media/Study/project_work/splitting_merging/radc_try1/radc1.ko] undefined! But during the "insmod" step, the module is not getting inserted into the kernel saying that there is an undefined symbol in the .ko file of the module. dmesg O/P : adc1: Unknown symbol __fixsfsi (err 0) radc1: Unknown symbol __umoddi3 (err 0) radc1: Unknown symbol __udivdi3 (err 0) radc1: Unknown symbol __floatundisf (err 0) radc1: Unknown symbol __umoddi3 (err 0) radc1: Unknown symbol __udivdi3 (err 0) If anyone can help me with tackling these errors, it would be really helpful...... Regards, Gaurav

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how opensolaris stores the major number ?
by Deepen Mehta Jan. 5, 2011

Jan. 5, 2011

Hi, zfs_mknode is the function use by mknod syscall to create device special file in solaris kernel. I traverse the code and just found how they stores the minor number which is in znode's(disk inode of Linux) attributes struct called sa_bulk_attr field uint16_t sa_buftype which is of 16bit only. so, it just store minor number in this field. And I am failed to understand where/how the solaris exact stores major number from code traversing. so, can somebody clarify where/how the major number stores in solaris code or in znode(disk inode). the source is available online and following link is of zfs_znode.c file having zfs_mknode function... http://src.opensolaris.org/source/xref/onnv/onnv-gate/usr/src/uts/common/fs… Regards, Deepen Mehta

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get info in a loop from a sysfs entry
by Wouter Simons Jan. 5, 2011

Jan. 5, 2011

Hi all, This might be a silly question, but I want to make sure I understand things correctly. I have a driver with a sysfs entry to get the next data sample every time I read the file. Used like below it works wonderful: # cat next 0x15814 # cat next 0x1682B The last 12 bits are the sample and the first (20) bits are the channel the sample is from (some ADC hardware board with 24 inputs). Now I have some C code that will loop periodically to collect the samples and do some magic with them and I was hoping I could simply keep a FILE * open with a loop like this: for (i = 0; i < count; i++) { if (fscanf(fd_next, "0x%X", &sample) != 1) { /* No data */ continue; } channel = sample >> 12; adc_data = sample & 0xFFF; if (channel > 23) { /* Sample out of range */ error_helper("ADC sample out of range", 0x32000010, 0); continue; } a_in[channel] = adc_data; fseek(fd_next, 0, SEEK_SET); } The problem is that after storing 1 sample, the next samples are never getting updated. I suppose the last line (fseek) does not cause the sysfs function to be called again as I hoped. But the sysfs documentation in the kernel says: If userspace seeks back to zero or does a pread(2) with an offset of '0' the show() method will be called again, rearmed, to fill the buffer. Can anyone tell me what I might be doing wrong? Wouter

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Kernel compilation
by scott Jan. 5, 2011

Jan. 5, 2011

I'm new to the list and would like to say hello to everyone. Now on to the meat. I have tried to compile a kernel with a grsec patch 5 times now using a couple of different methods and I keep getting a "No init found" and "Couldn't support optional features" errors every time at bootup. I'm trying to use a vanilla 2.6.32.27 kernel on 10.04 Ubuntu and it compiles fine, just will not boot. I've tried "CONCURRENCY_LEVEL=`getconf _NPROCESSORS_ONLN` fakeroot make-kpkg --initrd --append-to-version=-custom kernel_image kernel_headers", "CONCURRENCY_LEVEL=3 make-kpkg --initrd --append-to-version=-586 kernel_image kernel_headers modules_image". I have all the reqs for building kernels such as build-essentials, fakeroot, kernel-package, kernel-wedge, nurces-dev and qt for xconfig. These are the steps I've taken. DL the kernel image from kernels.org, get the patch from grsec.net, untar the kernel, cd into the directory created, do a 'cp /boot/config-`uname -r` .config', 'make oldconfig', apply the patch, then either 'make menuconfig' or 'make xconfig'. Then I do a 'make-kpkg clean' and run one of the commands in the first paragraph above. I get the debs built and can install them just fine, but I keep getting the same errors. I've cut out as many "Experimental" options I thought might cause a problem and still get a kernel panic at boot. Anyone have a clue what I'm doing wrong? Scott

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fixed memory bytes
by mohit verma Jan. 5, 2011

Jan. 5, 2011

hi all, i have seen many places in kernel where the variables specially the structures should be of fixed size independent of the architecture. i went through the definitions of them but dint get clearly (or frankly say ...dint get them even a bit) . so ,can please someone help me to understand this?? thanks in advance for help........ -- ........................ *MOHIT VERMA*

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Adding Module to kernel
by Praveen kumar Jan. 5, 2011

Jan. 5, 2011

Dear All, I have a kernel module which i want to add to kernel permanently(I was doing it dynamically) . How can we achieve this ? Regards, Praveen

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