Disable driver/module loaded by the Kernel while booting - linux-device-driver

When my embedded Linux OS boots up the driver st_drv and btwilink are getting loaded ,But I need to load the modules in a specific order ,which is as follows..
First load st_drv module (modprobe st_drv)
Run a application called uim in /usr/sbin
Load the btwilink module (modprobe btwilink)
I've looked /etc/modules or /etc/modules.conf file but no name of the above modules is present there
How can I disable these two driver/module loaded by the Kernel while booting itself?
NB: I use linux 3.12 kernel which uses Device tree

For this,
You can move the modules from the default path and then create a new module dependency,
go to /lib/modules/your_kernel_version/kernel
Generally your_kernel_versoin would something similar 3.4.23-generic
Locate the modules st_drv and btwilink from that directory, then move those to some other folder.
Create a new dependency list with the other modules using the depmod command
$ depmod .
Now you can reboot your PC and be sure that the drivers st_drv and btwilink are not loaded, verify using lsmod
Note: make sure you have root user permission

Related

Debian package: Is there an alternative to creating a symlink inside the user's home folder?

I'm developing a free guitar VST plugin that I want to distribute through a .deb package.
In the postinst script, I run the xdg-desktop-menu command to create the launcher for the standalone version (which works fine), but DAWs (like reaper and bitwig) will look for vst plugins inside $HOME/.vst and obviously won't find my plugin there.
At first I thought I needed to create a symlink inside $HOME/.vst but now I know debian packages aren't supposed do anything inside the user's folder. So what should I do instead?

-sh /usr/local/sbin/wpa_supplicant no such file or directory

I have built the TI wilink utilities which then I have integrated in my rootfs. This done using petalinux 2016.4 and have created a install template app in yocto build to copy all the tools and libraries in the rootfs.
When I bring up the BOOT.bin and image.ub, I see the files and libraries but when I try to run for example wpa_supplicant it does not work
even wpa_supplicant -h wont work.
It shows me error:
-sh: /usr/local/sbin/wpa_supplicant: no such file or directory.
The file is present and also has executable permissions.
Do you have any idea why it is not able to run ?
Thanks
Typically, this means that executable file is built for the wrong architecture, i.e. there is a mismatch between the environment where are you running and environment for which you are building. This is how you can make sure they do match or not (execute on target):
# file /usr/local/sbin/wpa_supplicant
...
# uname -m
...
If you see mismatch, then it all boils down to how are you building TI wilink.

Installing an perl based web-app in extremely restricted environment

Because i have a long series of comments with #ikegami, I cleaning up the question, in a hope it will be more understandable. Unfortunately, english isn't my "main" language. :(
Let say, having an environment where:
no development tools are installed (no make, nor gcc or like)
perl is installed with its core packages, nothing more
no outgoing network access is allowed - e.g. the user couldn't use curl nor cpan to download/install perl dependencies
the user even doesn't have admin (root) rights
but want install and evaluate some perl based web-app, let call it as MyApp
The MyApp
doesn't uses any XS-based module. (at least, I hope - in the development me using plenv and cpanm, so never checked the installed dependencies in depth)
it is an pure PSGI app, the simple plackup app.psgi works OK
the app uses some data-files which should be included in the "deployment".
The main question is: how to prepare the MyApp, and the all used CPAN-modules, to be easily installed in such restricted environment?
The goal is:
i don't need save my efforts and my time
but i want save the user's time and want minimize the needed actions on his side, so the installation (deployment) should be simple-as-possible.
E.g. how to get an running web-app to the user's machine with minimum possible (his) steps.
- the simplest thing is could be something as:
- copy one file (zip, or tarbal)
- unpack it
- from the terminal execute some run.pl in the unpacked directory.
To get the above simple installation, my idea was the following:
1.) Create an tarball, and after the unpacking will contain 3 folders and 1 perl-script, let say:
myapp_repo/
myapp_repo/distlib #will contain all MyApp's perl modules also ALL used CPAN modules and their dependecies
myapp_repo/datafiles #will contain app-specific data files and such
myapp_repo/install.pl
myall_repo/lib #will contain modules directly used by the `install.pl`
2.) I will develop an install.pl script, and it will be used as the installer-tool, like
perl install.pl new /path/to/app_root
and it will (should):
create the all needed directories under the /path/to/app_root (especially the lib where the will install the perl modules)
will call "local" cpanm internally (from the myapp_repo/lib) to install the app's perl modules and their CPAN dependencies using only distribution files from the distlib.
will generate and install the needed runtime script and the app.psgi into the /path/to/app_root/bin
will install the needed data-files for the app.
3.) So, after this the user should be able to simply run:
/path/to/app_root/bin/plackup /path/to/app_root/bin/app.psgi
In short, the user should use:
the system-wide perl and the system-wide perl-core modules
and any other
runtime perl-scripts (like plackup)
and the required CPAN-modules
should be installed to an self-contained directory tree using only files (no net-access).
E.g. the install.pl should somewhat call internally the cpanm to achieve (as equivalent) for the following cpanm command
cpanm --mirror file://path/to/myapp_repo/distlib --mirror-only My::App
which, should install My::App and all dependencies without network access using only the files from the myapp_repo/distlib
Some questions:
Is possible to use cpanm (called as an locally installed module) without the make?
For creating the myapp_repo/distlib, me thinking about using Pinto. Is it the right tool for achieve the above?
forgot me something? or with other words:
Is the above an viable (read: working) way?
are are any other tools, which i could/should to use for simplifying the creation of such distribution tarball?
#ikegami suggesting some method:
- "install everything" in one fresh-directory on my machine
- transfer this self-contained directory to the target machine
It sound very good, because this directory could contain all the needed app-specific data-files too, unfortunately, I don't understand the details how his solution should be done.
The FatPacked solution looks interesting too - need learn about it.
Don't write your own make or installer. Just copy it make from a different machine (which is basically what apt/yum/etc do anyway, and which you'd have to do even if you wrote your own). You'd be able to use cpan in 5 minutes!
Also, that should allow you to install gcc if you need it (e.g. to install an XS module), although it doesn't sound like you do. If you do install gcc, I'd install my own perl to avoid having to deal with PERL5LIB.
Tools such as minicpan will allow you to install any module from CPAN without internet access. Of course, you can keep using the command you are already using it if mirrors the packages you need.
The above explains how to simply and quickly setup a machine so it can use cpan and thus install any module easily.
If you just want to install a specific module and its dependencies, you can completely avoid using cpan on the target machine. First, you need a fresh install of Perl (preferable of the same version as the one on the target system). Then, simply install the module to a fresh dir on your machine, and transfer that dir to the target machine. That's it; nothing else needs to be done. This even works for XS modules if the two machine are similar enough.
This is what ppm (ActiveState's Perl package manager) does.
Unfortunately, while this solution is almost as simple as the one above, it's not nearly as flexible, it doesn't run the test suite of the modules being installed, etc. It does have the advantage of not requiring the transfer of any binary (if you're not installing any XS modules).

Not able to install the Perl module Device::USB on Windows

I need to run a perl program on Windows. I install Strawberry Perl.
I am not able to install Device::USB module.
Here is the revelant error in log :
-> OK
Successfully installed Inline-0.80
Installing C:\Dwimperl\perl\site\lib\MSWin32-x86-multi-thread\.meta\Inline-0.80\install.json
Installing C:\Dwimperl\perl\site\lib\MSWin32-x86-multi-thread\.meta\Inline-0.80\MYMETA.json
Configuring Device-USB-0.36
Running Makefile.PL
ERROR: Missing required environment variables to compile under Windows.
LIBUSB_LIBDIR should contain the path to the libusb libraries
LIBUSB_INCDIR should contain the path to the libusb include files
-> N/A
-> FAIL Configure failed f
As the error msg states, you should define the two environment variables LIBUSB_LIBDIR and LIBUSB_INCDIR.
Under windows on the command line you can add env vars (temporarily, for the currend cmd process) via SET name=value, e.g.: SET LIBUSB_LIBDIR=C:\your\path\to\the\libs.
Also, libusb has to be installed on your machine - maybe this also will set the lib&include path env vars permanently. (thx for comment! :)
First, you need to install the libusb library on your system.
Device-USB
This module provides a relatively complete Perl wrapper on the libusb
library. Using this module provides an object-oriented interface to any
installed USB devices.
Obviously, the module requires a copy of the libusb library compiled for the
target system. The module also requires a C compiler compatible with the
Perl installation, because it uses the Inline::C module to create the
interface to libusb.
Then, you need to tell Device::USB where to locate the library by setting env var LIBUSB_LIBDIR to the directory that contains the libusb DLL, and by setting env var LIBUSB_INCDIR to the directory that contains the libusb .h files.
You can set those env vars by right-clicking "My Computer", clicking "Properties", clicking "Advanced system settings", clicking "Environment Variables".

Building modules with linux kernel for custom flavor

I followed the instructions given in the link: http://blog.avirtualhome.com/how-to-compile-a-new-ubuntu-11-04-natty-kernel/ for building a custom kernel and booting it. Everything works fine, except that when building it, I used the option skipmodule=true (as given in this link), so I guess the modules are not built for this kernel. So I have two questions:
How do I build only the modules for my flavor, now that I have the rest of the kernel built? 'make modules' will build it for generic flavor only, if I'm not wrong.
Also does it require me to build the entire kernel source, 'fakeroot debian/rules binary-i5' (i5 is my custom falvor), each time I make a change to one of my modules?
Thanks.
1) To build a linux kernel module for a specific kernel from the module source directory do:
make -C {path-to-kernel-source} M=`pwd` modules
The -C option tells is used to point to the kernel source tree where it finds the kernel's top-level Makefile. The M=`pwd` option points it to the module source directory, where it builds the 'modules' target.
2) Nope, its not necessary to build the source kernel. Either having the kernel source tree or the kernel headers suffice.