I am using Petalinux, built with Yocto SDK. I want to automatically install my kernel module and make the devices available in /dev/*.
With KERNEL_MODULE_AUTOLOAD+="modulename" I can see the appropriate entries in /etc/modules-load.d/ as well as entries in /sys/class/misc/** , but not in /dev/*. Is there something I am missing?
Well, the structure of Yocto has nothing to do with the creation of device nodes. Either your driver does that for you (upon loading / probing), or you had some script that made them earlier. As long as your module has been loaded upon boot, you've got KERNEL_MODULE_AUTOLOAD correctly. If the module gets loaded, but you're not getting any device nodes automatically (and you got that before) you'll need to investigate what has changed in your system. (Versions of kernel and eg mdev/udev etc)
Related
I am desperately searching for two weeks at least now on how to build any linux using yocto and boot it via syslinux afterwards.
My current approach is to build the core-image-minimal-initramfs, I am using the bzImage as the kernel and the rootfs as the initramfs.
So after bitbaking it is something like this:
KERNEL bzImage.bin
APPEND initrd=rootfs.cpio.gz
Unfortunately, it doesn't work like this. I got a ton of different errors on all my approaches. The kernel is always loaded correctly, but I am having a lot of issues using the initramfs. Sometimes it is just not loading it, sometimed it is complaining about a missing rootfs.img on \dev\sda1,...
Is there anyone that could explain to me how this kind of thing works? At best by giving a working example to start somewhere.
The Yocto community seems not to be very engaged helping newbies.
Background
I just developed my first flutter desktop app for a windows machine. The app is working fine while developing/debugging it, but I am trying to test it as an application in release mode.
What’s done
I created an msix using pub msix.
For signing, I have tried both my
own certificate and the test certificate that comes with msix
packages by default.
I have tried both stable and beta channels.
Actual Problem
When I install the app on the other system (or even on the actual system where I debugged the app). I can install the msix setup successfully I can see my app listed in the apps, but when I try to open it, it is stuck on a blank/white screen. There is no UI rendered. And if I try to maximize the window, it goes to App not responding state.
Any help will be really appreciated.
Thanks in advance.
Update / New Finding
After going through the links provided by Yehuda Kremer and pulling my hair for a few days, I found the answer in this tweet
https://twitter.com/FilledStacks/status/1436280577439715338?s=20
So the main issue is that app is using some absolute paths that don't work on other machines (after release)
1- My app was using a database, so I have made sure that that database path is relative to the application document directory.
2- Now the build is also referring to some dependencies and their paths are also absolute. I have noticed a flag CMAKE_INSTALL_LOCAL_ONLY in the cmake_install.cmake but that flag is not being set anywhere.
Here is the log of flutter build windows -v
https://pastebin.com/LAeshUMY
-- Now I am looking for a proper way to convert all the paths to relative so that the build is ready for installation on different machines, instead of local installation only.
I have found the solution.
The main problem was that the app was looking for some dependencies and it was unable to find them. As mentioned here.
The reason for not finding that in release mode can be one of the following,
You are using some dll (package that depends on a dll) that is available on a specific path in your system, but when you are release the app that (absolute) path is not valid anymore.
You are adding some asset with absolute path (that is only applicable to your system).
Solution:
If it is a dll, you should be adding that to the release folder. In my case it was sqlite3.dll
If it is some other asset then you should always use the relative path.
You mentioned msix package, let see if the problem is in the app or in the packaging process
run flutter build windows without the flutter pub run msix:create, then run the created .exe file to see if its work.
btw this issue mention here: https://github.com/flutter/flutter/issues/74507
and here (the 'maximizing' problem): Black screen appears on maximizing and minimizing flutter desktop app
Good day,
I have an application that I developed that transfers files between two machines ("site" and "server"). This application was set to target dotNet 3.5. Furthermore, I am using Renci.SshNet to handle the connections between the machines and the transferring of said files.
The issue that I am facing currently though is that about 70% of the "site" machines do not have a standard dotNet and is also quite old; thus these machines do not support all the required functionality as the external dll makes calls to System.Threading.WaitHandle.WaitOne() and System.Threading.WaitHandle.WaitAny(WaitHandle[], Int32) and other overloads of these methods.
The workaround that I have for this though is to install netfx20SP2 or netfx30SP1, yet I am not in the position to perform this update on all machines as they are scattered across the country and have data limitations (bandwidth and cap).
What I want to do possibly is to embed the System.Threading dll that I have downloaded and then the application should use those classes instead, or alternatively just point the application to use the said dll.
Is this at all possible, or do you have to load the dll into the GAC? And also, will it be possible to "run" this higher version of System.Threading in the application while the system itself is on a lower framework version. Something is telling me that the best bet will be to actually run the service pack installation to avoid unnecessary coding but I'm not sure exactly how to approach this.
Thank you in advance for any assistance / suggestions,
JD
To allow the execution of an application that, let's say, targets .Net 4; while the machine itself only has let's say, .Net 3.5, installed, one can redirect Windows to check the local (executing) directory for dlls that should contain the required symbols loaded into memory instead of the default symbols that get loaded upon execution (the default would be the NetFx installed on the machine - which I believe the highest version of the framework that can be found upon loading when the execution starts or would be the highest available version that is lower or equal to the targeted framework).
This file's contents (myApp.exe.local) are ignored. It is just there to tell Windows to
look in that folder for the applicable symbols and if not found, the system will roll back to attempt to load these symbols from the NetFx directory.
Read more at Microsoft Dev Center - Docs (link is attached to the following paragraph which is a Copy-Paste of a section of this document).
To use DLL redirection, create a redirection file for your application. The redirection file must be named as follows: App_name.local. For example, if the application name is Editor.exe, the redirection file should be named Editor.exe.local. You must install the .local file in the application directory. You must also install the DLLs in the application directory.
Can an EFI application be automatically loaded and executed before BDS phase, just after all the DXE drivers have been loaded?
If I include the application in .fdf file just after the DXE drivers, will it be automatically loaded and executed ?
This question is very board and I will only scratch the surface with my answer. Please read documentation that I mentioned to get more information.
If you have full source code of UEFI firmware for your hardware then you can add UEFI module to be executed before BDS phase. Otherwise you can affect only boot order (which is right before calling ExitBootServices) by adding UEFI Application using bcfg shell command, pleas check this question.
If you want to execute code before BDS it have to be DXE module (ie. DRIVER, RUNTIME_DRIVER). There are many module types that can be used and exact depend on your use case. More about module types you can find in Appendix G of INF file specification.
Adding to FDF file is not enough for code to be executed. FDF file describe only flash layout: how and where each binary would be placed in final flash image. To add DXE driver you also have to add your INF file to platform DSC file. Next thing is to have correct [Depex] section in INF, which can be as simple as:
[Depex]
TRUE
Last thing that you have to understand is DXE Dispatcher. Each boot DXE Dispatcher iterate over know image list and and call EFI_DRIVER_BINDING_SUPPORTED function (defined by EFI_DRIVER_BINDING_PROTOCOL). This method should check if supported hardware is available in platform. If EFI_DRIVER_BINDING_SUPPORTED return success then other driver binding method will be called (EFI_DRIVER_BINDING_START), which starts device. Entry point should be used only for protocol registration, starting device in entry point is not recommended.
Useful resources:
EDK II Specifications - specs for various file types (INF, FDF, DSC, DEC, etc.)
Developer Resources - Drivers Writers Guide and Drivers Wizard.
EDK2 sourceforge - repository of very useful resources about EDK2
I have a PySide/Phonon app (developed for and working flawlessly on Windows) that I need to "port" to Mac OSX - where I have no development experience whatsoever.
The app works as expected if I just run the Python file - the problems arise when I try to package it (which I need to do) with py2app.
If I leave the resulting .app as is, Phonon doesn't work, because it fails to load the required phonon_backend ; if I add the plugin path to qt.conf, as various sources suggest, Phonon seems to load (that is, I don't get the corresponding error message anymore), but I start getting the "so-and-so library is loaded twice, one will be used, which one is undefined" error, and the app crashes right away.
Finally, if I try to use the macdeploy_qt tool, I receive a message to the effect of "no external framework" and the results are functionally equivalent to what I get without using the tool, except there are a few more plugins in the relevant directory.
Any ideas/pointers/tutorials/etc? I'm using PySide1.1.1 for Qt4.7, by the way, and Python.org python binaries (otherwise py2app can't even start to build a standalone app, it seems).
I suggest you do it like in this tutorial.
Then you just have to add the following line somewhere at the top of your main module:
QApplication.setLibraryPaths([os.path.join(os.environ['_MEIPASS2'], 'qt4_plugins'), os.environ['_MEIPASS2'] ])
For PyInstaller >1.5 the following code should be used instead:
QApplication.setLibraryPaths([os.path.join(sys._MEIPASS, 'qt4_plugins'), sys._MEIPASS])