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Fw: new important message
by bear.yogi＠gmx.de March 3, 2016

March 3, 2016

Hello! New message, please read <http://majorinvesting.com/longer.php?drpr> bear.yogi(a)gmx.de

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Question : How to access to bandwith statistics from kernel space?
by Martin Houry March 2, 2016

March 2, 2016

I have made some research and I could't find a library who can give me interfaces's statistics like max/min/average bandwidth, jitter, ... Do you know a way to do this? Thank you Martin

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Project Idea..
by SUNITA March 1, 2016

March 1, 2016

Respected Sir/Madam, I am trying to study the effect of Scheduler Policies on Energy Consumption of Portable Device. This will be achieved by modifying the current Completely Fair Scheduler by changing the range of nice values from 40 to 100 and adding a new scheduing policy. CFS uses SCHED_RR, SCHED_FCFS, SCHED_OTHER, SCHED_BATCH Policy for scheduling any process. The idea is to insert a new scheduling policy by modifying the header files. Can this be a good topic to carry out research.I welcome any other idea related Linux Kernel CFS. Regards, SUNIITA

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Regarding Linux Kernel Upgradation
by Anil Nair March 1, 2016

March 1, 2016

Hi All, A little confusion, I have existing Linux kernel version 4.5rc4 I wanted to upgrade my Linux kernel 4.5rc6, The preferred method is step by step patch,first apply patch-4.5rc5 and then patch-4.5rc6, Then recompile the kernel. Is this is the right approach? Or am I missing out something? -- -- Regards, Anil Nair

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How to understan /proc/sys/kernel/sched_domain/cpu$/domain$/flags?
by Nan Xiao Feb. 26, 2016

Feb. 26, 2016

Hi all, I find there is a flags file under /proc/sys/kernel/sched_domain/cpu$/domain$ directory, but can't figure out the meaning of this file: # cat flags 687 Could anyone tell me where I can find the definition of this file? Thanks in advance! Best Regards Nan Xiao

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Mutex and Spinlock locked together
by priyaranjan Feb. 25, 2016

Feb. 25, 2016

Hello All, Do you have any idea of a situation where we would need mutex and spinlock to be locked together? I think there is an example for this in Linux kernel. Can anyone help me? Regards, Priyaranjan

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Is there a bug in dgnc.ko?
by Navy Cheng Feb. 25, 2016

Feb. 25, 2016

Hi, My kernel version is v4.4, and I have built drivers/staging/dgnc/dgnc.ko. I change to *dir*/drivers/staging/dgnc and do like this: sudo insmod ./dgnc.ko sudo lsmod | grep dgnc sudo rmmod ./dgnc sudo insmod ./dgnc.ko After I re-insmod the dgnc module, my laptop is breakdown. My OS is debian 8.0. Is there a bug in dgnc.ko or something wrong with my OS or kernel. If there is a bug, How can I find it? Thanks.

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user rsyslog/syslog
by Ran Shalit Feb. 24, 2016

Feb. 24, 2016

Hello, I am trying to write to rsyslog from application. With openlog(..., LOG_USER), it works fine and I find the log in /var/log/user.log (it is defines in /etc/rsyslog.d/50-defaults.conf ) But we need to enable different applications to have each its own log file. I tried to use LOG_LOCAL0 instead and configured it in /etc/rsyslog.d/50-defaults.conf the same way as user: local0.* action { type="omfile" FILE="/var/log/local0.log" FileOwner="root" FileGroup="adm" } I then did 1. /etc/init.d/rsyslog stop 2. /etc/init.d/rsyslog start I see no warnings or errors, and I started the application trying to write to LOG_LOCAL0, But there is no new file created, no logs. Is there any idea whatws wrong, or how I can achieve this multi user's logs ? Thank you, Ran

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Does Linux kernel disables any Interrupts while going into IRQ handler?
by priyaranjan Feb. 24, 2016

Feb. 24, 2016

When an Interrupt occurs most device drivers creates a critical section using spin_lock_irqsave or spin_lock_irq which disables the interrupt. In such a case the Interrupts are disabled by the IRQ handler. My question is whether Linux kernel disables any interrupts just when the IRQ handler executes or it just wait for the IRQ handler programmer to disable the IRQ in whatever way? My understanding is that Russel King has implemented IRQ_DISABLED, If this flag is set then only the IRQ that has occurred is disabled lately however enabled automatically by Kernel after IRQ handler finishes. Is that correct? This also happens in delayed manner.Can anyone explain me how exactly the IRQ disabling is delayed? >From free-electrons link <http://free-electrons.com/kerneldoc/latest/DocBook/genericirq/Highlevel_IRQ…>, what I read is :- *The interrupt is kept enabled and is masked in the flow handler when an interrupt event happens*. This prevents losing edge interrupts on hardware which does not store an edge interrupt event while the interrupt is disabled at the hardware level. Can anyone please explain the bold line here? Regards, Priyaranjan

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Re: Porting to an S3C2416 failed with no console message
by Woody Wu Feb. 24, 2016

Feb. 24, 2016

On Wednesday, February 24, 2016, nick <xerofoify(a)gmail.com> wrote: > > > On 2016-02-23 09:35 AM, Woody Wu wrote: > > Hi, > > > > I am trying to port 3.18 kernel to a S3C2416. Years ago, a guy helped me > > ported a 3.1.0 kernel to the same board, and the guy left and the kernel > > got too old. The guy also ported an u-boot as boot loader to load the > 3.1.0 > > kernel. I had the source code of the ported u-boot and the 3.1.0 linux. > > > > Now, my problem is that my porting of 3.18 seems not working, I did not > see > > any kernel message printed to the first SoC serial port as I expected. As > > long as I can get kernel message printed to the serial, I think I can > step > > by step finish the whole porting work eventually. But now, there is no > > message and I have no other hardware debugging tools and knowledges, I > felt > > I lost my way totally. > > > > I hope someone can give me some suggestions, clues to help me > > understand where to check and what's the possible causes. > > > Firstly my knowledge with kernel upstream porting to a non mainlined > port is not as good as some of the other people here but let's see what > I can do. > Since I found the old porting of the 3.1.0 is quit similar to SMDK2416, > > then I started my work from also the SMDK2416 board code in 3.18. > > Basically, I defined the machine-code to match that passed from u-boot, > and > > copied the MACHINE-START definition section with removing of some > > not-immediately-needed stuff such as USB, NAND and HMSUI etc. I also > > enabled the S3C2410 serial driver and enabled the serial console > supporting > > for the Samsung SoC. Of course, I had the kernel parameter of > > "console=ttySAC0", ttySAC0 is the Linux device name of the first UART > port > > in the SoC. These are basically what I had done and I guess the SoC > serial > > part between my board and SMDK2416 should be very similar and the kernel > > should at least be able to print it's first message then I should have > > chance to fix other differences. But there is no kernel message at all > as I > > mentioned above. > > Can you either send me the patch series that the other developer used to > port > your port to 3.1.0 or I would recommend stating on kernel 3.1.0 as it's > still > a longterm kernel unless you have reason to upgrade. If you do I would > recommend > you either get something with experience or yourself to try and upstream > the > differences between your board and the mainline so others will not have to > do > the same work as you unless your company will not allow you to do this. > > What should I check for the problem usually? Is there a checking list to > go > > through? I hope you experts can give me some clues. Thanks in advance! > > To make a patch, I have to have the original 3.1.0, but I was confused about how the kernel.org organized, I just cannot find how to get a 3.1.0 tarball or git repository. Can you please give me a hint? BTW, I also dont really understand what the 'mainline' mens. If I download a latest 3.18.27.tar.xz, is it a mainline? > Their are two things you can do here either try and enable early_printk as > this > seems to be happening before the serial console is able to print the first > kernel > message. The second is trying to enable kgdb on the board and use another > computer > over the serial port to do this sort of debugging. > Hope this gets you started, > Nick Firstly, I will try early_printk soon. Before that, can your tell me what are differences betweenthe following printing technologies: 1, early_printk 2, early_print, 3, putc used in arch/arm/compressed/misc.c. Secondly, I have a question about kgdb. You see the situation is that my serial port had been initialized by the u-boot, but not yet touched by the kernel since the kernel is not yet run and waiting for debugging, and now I am jusr sitting in the u-boot command prompt and has an uImage kernel image file loaded in a region of SDRAM, do you think that these all above are enough or possible to the kgdb debugging? Many thanks! > Best Regards, > > woody > > > > > > > > > > _______________________________________________ > > Kernelnewbies mailing list > > Kernelnewbies(a)kernelnewbies.org <javascript:;> > > http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies > > > -- Life is the only flaw in an otherwise perfect nonexistence -- Schopenhauer woody public key at http://subkeys.pgp.net:11371 (narkewoody(a)gmail.com)

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