Re: unlikely compiler flag propagation

Hi Greg, hi all, 2015-02-18 19:24 GMT+01:00 Greg KH : > On Wed, Feb 18, 2015 at 07:09:47PM +0100, Matthias Brugger wrote: >> Hi all, >> >> I have a question about the unlikely compiler flag. >> When a called function is only returns an error with the unlikely fl

unlikely compiler flag propagation

Hi all, I have a question about the unlikely compiler flag. When a called function is only returns an error with the unlikely flag set, should I set the unlikely compiler flag for the return value check in the callee as well? For example: int function_one(int *list, int num_elements) { int i

Re: x86_64_defconfig and i386_defconfig: What is the difference?

On 09/09/14 09:58, Rajat Jain wrote: > Hi, > > Can someone tell me if the i386 one is to be used when we want to build for a > 32bit machine and the x86_64 is to be used for 64 bit machine? You can build the kernel with any architecture for any architecture. This is called cross-compiling. The

Kconfig set default macro bug?

Hi all, I'm just playing with the early printk macros of the low level printk. The address of the UART port is set to a default value [1]. So if you save the config and then enter again in menuconfig, you are not able to change the value to a different default value (I suppose because Kconfig see

Re: DTS: clock not found

Hi Javier, 2014-02-06 Javier Martinez Canillas : > Hello Matthias, > > On Wed, Feb 5, 2014 at 6:02 PM, Matthias Brugger > wrote: >> Hi, >> >> I'm stuck with dts problem. Whenever I try to find a clock for my >> device, the of_get_clk returns an error

DTS: clock not found

Hi, I'm stuck with dts problem. Whenever I try to find a clock for my device, the of_get_clk returns an error "Kernel panic - not syncing: Can't get timer clock" My DTS looks like this (reduced to relevant parts for easier reading): #include #include #include "skeleton.dtsi" / { [...] s

Re: ARM Linux and ATAGS

El dia 09/01/2014 8:48, "Mj Embd" va escriure: > > Hi, > > What are atags and are they still used after addition of device tree in linux ? Afaik atags is the mechanism how the kernel gets the boot parameter from the bootloader. In the kernel config you can decide if you will use the boot paramete

Re: Introducing Myself, Looking to Learn

2013/9/3 Robert P. J. Day : > On Tue, 3 Sep 2013, valdis.kletni...@vt.edu wrote: > >> On Wed, 04 Sep 2013 02:05:42 +0530, Varad Gautam said: >> > Hi Vladis! Thanks for replying. I think I would be fine with >> > writing real code once I figure out what goes where. >> >> Well, assuming you have a ba

First userspace executalbe run at boot up

Hi all, I'm actually reading the init/main.c source code to understand which is the first user space program the Linux kernel runs. As far as I understood it: 1. tries to execute the file defined by the rdinit= kernel parameter and sets it to "/init" if the parameter is not given 2. tries to exec

Re: pulling in patches mentioned in mails (linux-ker...@vger.kernel.org)

El 25/07/2013 5:14, "kernel neophyte" va escriure: > > Hi, > > I am sorry if this has been asked before, I tried to look around but did not get an solution and hence the mail. > > In this mail from Mel Gorman: > > https://lkml.org/lkml/2013/7/15/362 > > He mentions a set of patches: > > https://lk

Re: Memory leaks in Samsung's kernel

El 28/05/2013 19:16, "Michał Akaanonim" va escriure: > > Hi, > I'm developing custom kernel for my Samsung Galaxy Ace 2 phone. > First, I'd like to check if there are any bugs, so I built kernel with kmemleak enabled and I get 10 entries, for example: > > unreferenced object 0xce2a2000 (size 8192)

Re: how do i read a block

El 13/05/2013 10:07, "shampavman" 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 do it? > > read(fd, buf, 4096) ; > would this mean i would read the first block and all its contents? You

Re: [help] kernel oops in function gpio_to_irq

El 27/03/2013 18:16, "Mylene Josserand" va escriure: > > Hi everyone, > > > I have a problem with gpio functions. > My kernel version is 3.8.2 and my SoC is a imX27 on a "home-made" board. > > First, when I boot, I had only the "Starting kernel..." message. > So I rebuild my kernel with CONFIG_DEB

Re: BFQ: simple elevator

2013/3/25 Raymond Jennings : > On Sat, Mar 23, 2013 at 9:42 AM, Matthias Brugger > wrote: >> On 03/23/2013 01:05 AM, Raymond Jennings wrote: >> >> On Fri, Mar 22, 2013 at 2:20 PM, wrote: >> >> On Fri, 22 Mar 2013 13:53:45 -0700, Raymond Jennings said: >&

Re: BFQ: simple elevator

On 03/23/2013 01:05 AM, Raymond Jennings wrote: On Fri, Mar 22, 2013 at 2:20 PM, wrote: On Fri, 22 Mar 2013 13:53:45 -0700, Raymond Jennings said: The first heap would be synchronous requests such as reads and syncs that someone in userspace is blocking on. The second is background I/O l

Re: BFQ: simple elevator

On 03/20/2013 10:41 PM, Raymond Jennings wrote: > On Wed, Mar 20, 2013 at 2:03 PM, wrote: >> On Thu, 21 Mar 2013 02:24:23 +0700, Mulyadi Santosa said: >> >>> pardon me for any possible sillyness, but what happen if there are >>> incoming I/O operation at very nearby sectors (or perhaps at the sam

Re: Android Kernel Compilation

2013/1/30 Rahul Gandhi : > I am trying to compile Kernel for my Android device. I am using the NDK > Toolchain (arm-linux-androideabi-4.4.3). When I use the defconfig, the > kernel compiles without any errors but when I flash it onto my device, it > either gets stuck on the HTC logo or continuously

Re: guides to board files -> device-tree and Android -> mainline?

Hi Paul, 2013/1/26 Paul Wise : > Hi all, > > Are there any guides for developers new to Linux for: > > * converting board files to device-tree > * porting drivers and patches from Android to current mainline? there are several parts of Android, which are not part of the mainline kerne

Re: can I input a gate service to kernel to get kernel data to user ?

Hi, On 12/14/2012 01:53 AM, horse_rivers wrote: > At 2012-12-13 18:52:53,"Matthias Brugger" wrote: >> On 12/13/2012 04:17 AM, horse_rivers wrote: >>> is there method for doing this work? take kernel data to user? >> >> I think copy_to_user is what

Re: can I input a gate service to kernel to get kernel data to user ?

On 12/13/2012 04:17 AM, horse_rivers wrote: > is there method for doing this work? take kernel data to user? I think copy_to_user is what you are looking for: http://lxr.free-electrons.com/source/include/asm-generic/uaccess.h#L253 Cheers, Matthias > > > thanks! > > __

Re: Find out function arguments value from stack pointer

On 12/12/2012 12:24 PM, Manavendra Nath Manav wrote: > On Wed, Dec 12, 2012 at 4:38 PM, Fabio Pozzi wrote: >>> When i call print values at offsets starting from >>> __builtin_frame_address (0) the function arguments start from offset >>> 2. How can I confirm that this behavior is always consisten

Re: Best and fastest way to understand kernel subsystem ?

On 12/06/2012 10:54 AM, Shraddha Kamat wrote: > What is the best (and the fastest ) way to understand a kernel > subsystem ( for e.g., filesystem , Networking .. etc.) If you are a beginner it might be convenient to look on a small subsystem first. The filesystem is really big and complicated, I

system call numbers

Hi all, I'm looking into the avr32 architecture implementation, as compiling the kernel gives you several warnings about system calls which are missing. I had a look in the unistd.h file I realized that system call numbers differ widely from other architectures (I had a look at arm and x86). Ar

Re:

Hi, On 10/15/2012 11:24 AM, Niroj Pokhrel wrote: > Hi, > I'm new to linux and kernel . I'm ongoing with the linux device drivers. > I've followed the the book LDD but i'm lost about how to call my > driver's specific method from the user space. > Eg: if have developed a character device and insert

Re: Writing a new device driver

Hi Malice, On 06/25/2012 09:42 PM, Malice wrote: > Hi > > I'm planning to write a new device driver on linux kernel . The device i > intend to write will be a device that'll pipe the data coming into it to > another computer that'll be also having the same device . So in short > the device'll be r

Re: Missing Key-codes from input.h file.

On 06/26/2012 08:47 AM, Dharam Kumar wrote: > On Tue, Jun 26, 2012 at 12:02 PM, anish kumar > wrote: >> On Mon, 2012-06-25 at 23:24 +0530, Dharam Kumar wrote: >>> On Mon, Jun 25, 2012 at 10:47 PM, anish kumar >>> wrote: On Mon, 2012-06-25 at 18:52 +0530, Dharam Kumar wrote: > Hi, > I

Re: Kernel 3.4 compile problem

On 06/19/2012 02:43 PM, Kaan Akşit wrote: > Lieber Matthias, > > Vielen dank für ihre email :) Here is the English version of the output: > >DEPMOD 3.4.3 > DEBUG: return value for "make > INSTALL_MOD_PATH=/var/pisi/kernel-3.4.3-163/install/ DEPMOD=/bin/true > modules_install mod-fw=" is 0 > ..

Re: Kernel 3.4 compile problem

Merhaba, On 06/19/2012 01:11 PM, Kaan Akşit wrote: > Dear all, > > I am a newbie who try to solve a problem on compiling new kernel on my > computer. Here is the point where I am stuck; I can configure and > compile kernel without any error, but whenever I try to install libc > headers I keep rece

Re: A confusion about invoking my syscall

On 06/19/2012 06:32 AM, 王哲 wrote: > > > 2012/6/19 Jeff Haran mailto:jha...@bytemobile.com>> > > __ __ > > __ __ > > *From:*kernelnewbies-boun...@kernelnewbies.org > > [mailto:kernelnewbies-boun...@kernelnewbies.org >

Re: no-op error in dmesg

Hi, On 06/18/2012 08:34 PM, Pritam Bankar wrote: > Hi, > I have one structure called foo. Address of object of foo(say objfoo) is > passed to ioctl call > > status = ioctl(fd, arg, &objfoo); as objfoo is a pointer to foo: struct something foo; struct somethint *objfoo = &foo; &objfoo therefore i

Re: cross compile linux

On 02/11/2012 10:15 AM, Daniel Baluta wrote: > On Sat, Feb 11, 2012 at 9:05 AM, chromaticwt zac > wrote: >> what is the proper way to cross compile the linux kernel from one arch to >> another? specifically, >> i386 -> ppc. > > You should use a cross-compiler. I recommend you crosstool-ng. > Use

Re: blktrace vs ftrace

Hi, On 02/03/2012 06:59 AM, Mulyadi Santosa wrote: > > I could only offer this explanation: > blktrace traces events in block level. In this level, I/O is likely > serializedunless you have more than one physical disks. > > in ftrace, you see events right before it hits block level operation.

Re: Changes in block layer for IOScheduler Insertion selection

hmark. For flash file systems, David Wagner from Free Electrons developed a benchmarksuite. Maybe it would be worse having a look on it. Best regards, Matthias Brugger Thanks in advance.. On Mon, May 30, 2011 at 10:53 AM, mani <mailto:manish...@gmail.com>> wrote: Dear Eduardo

Re: blktrace vs ftrace

On 02/02/2012 07:15 PM, Mulyadi Santosa wrote: > On Thu, Feb 2, 2012 at 17:20, Matthias Brugger > wrote: >> Hi all, >> >> I'm trying to analize I/O behavior of Qemu on the host. > > what is your complete command to invoke Qemu? qemu -hda scheduler.raw -dri

Re: creation of blktrace completion messages

On 01/18/2012 02:59 PM, Matthias Brugger wrote: > Hi all, > > where does the kernel create the blktrace completion messages? the mesage is created in block/blk-core.c:blk_update_request which calls trace_block_rq_complete > > Is it done in the interrupt routine or in the block la

blktrace vs ftrace

Hi all, I'm trying to analize I/O behavior of Qemu on the host. I used blktrace and the blk tracer for ftrace but I see different I/O behavior. I use 4 threads in the VM each reading sequentially a file. Readahead is turned off. With blktrace reads are transmitted in a sequential way, which me

creation of blktrace completion messages

Hi all, where does the kernel create the blktrace completion messages? Is it done in the interrupt routine or in the block layer. I just found: register_trace_block_rq_complete(blk_add_trace_rq_complete, NULL); and register_trace_block_bio_complete(blk_add_trace_bio_complete, NULL); But I don't

Re: Guidance on writing device drivers

On 11/10/2011 05:26 AM, Prajosh Premdas wrote: > [...] > On Thu, Nov 10, 2011 at 10:08 AM, rohan puri > wrote: > On Wed, Nov 9, 2011 at 10:40 PM, suraj khurana > mailto:surajkhuran...@gmail.com>> wrote: > > Hi all, > I am a newbie in linux wor

Re: Create a one-to-many tunnel

Vimal schrieb: > Hi, > > I wish to create an IP in IP tunnel interface that works as follows: > > At the sender: > * The interface checks the dst IP address on the IP packet that it receives. > * It encapsulates the IP packet inside another IP packet with: >Field 1: source address = the inter

Re: Regarding Linux device driver Project

Hi, ashutosh mishra schrieb: >> hi >> i want to write a driver for DIO-48S PCI Card >> (its automation Project - Aluminium Foil Winding Automated System Using PCI >> Interface) >> i want to ask that what are the..prerequesite...for the Project... >> i hav konwledge of C,89c51 Microcontroller,Arm