I want to try programming for EFI so I created a VM using virtualbox, checked "enable efi" option and left CD empty.
The efi shell boots how it should but instead of FS0 i only see BLK0, BLK1 etc. Is there any way to have FS without inserting USB disk (which is displayed as FS)?
Edit:
Thanks for your replies. For people who still want to use VB - formatting VB disk with DISKPART using Windows CD solves the problem.
#unixsmurf answer in comments is correct. Your image need file system supported by UEFI. If you can't see fsX in output of map command then it means that non of attached block devices (blkX) contain supported file system. Please create FAT32 partition on your disk, then you will be able to see fsX in map output. To switch between file systems use DOS like syntax command ie. fs0: switch to FS0 file system.
According to UEFI specification 2.5 section 12.3:
EFI encompasses the use of FAT32 for a system partition, and FAT12 or FAT16 for removable
media.
I would suggest to use OVMF (Open Virtual Machine Firmware) directly with QEMU not through VirtualBox. Why ?
Because you can hack OVMF and learn how it works internally, this give you better understanding, VirtualBox hide internals and I'm not sure if it allow firmware replacement
OVMF was developed initially for QEMU and it is adapted by various other virtual machines, because of that there is much more support for OVMF on QEMU then OVMF on VirtualBox
using QEMU also give you ability to emulate your hardware and write drivers/applications in UEFI that use it
I wrote beginners tutorial that help setting up development environment needed for UEFI application development using OVMF.
More about OVMF.
Related
I've been going through the windows documentation for the Dism API with the goal of writing an exe in C++ (or whatever language can accomplish this) that can create a WIM image while running in Windows PE. I found a .NET Wrapper for the Dism API that seems like it might be useful for this purpose, but I'm unsure if a .NET app will successfully run in Windows PE. Overall, my problem is that I don't see a function that can create--and doesn't simply modify--a wim file.
If I didn't care about encapsulating this in an .exe file, the Dism documentation does show how to initially create a wim--which makes me curious why a similar function wouldn't exist within the api. Please advise if the simplest solution is to have my code call a function such as system() within the code.
To summarize, I'm looking for a way to create a wim file programmatically (called from executing an exe file) from within Windows PE.
As always, thank you for the help and advice.
I work on a project that works with DISM in WinPE quite a bit. We configure WinPE with all the .net packages as described here. Then WinPE can be configured to start an application.
I use c#, but you can do managed apps in c++ as I'm sure you know. I find putting c# code into WinPE substantially easier, but that's more a function of my experience, I suppose.
The main way we use to interact with DISM is run a command using System.Diagnostics.Process. The process runs in a separate thread, but the API is simple, and you can wait on (and/or timeout) your process for synchronization purposes. This just uses the DISM command line interface, although you can also use powershell cmdlets if you've added that package to your WinPE image. It may seem like a hacky "interface" from your app to DISM, but it works reliably, and you can keep the process window from showing up on the screen. This makes for a decent asynchronous platform for running bunches of windows imaging utilities, such as DISKPART, DISM and BCDEDIT.
The principal way you'd capture a new image is with DISM /Capture-Image. Sounds like you've already discovered this fact. Lots of options that are somewhat beyond the scope of this q/a, but I hope this gets you on a useful path.
Even though this post is a bit older, here is a possibly still relevant resource for you. Perhaps this one will help.
I've written a small GUI-based tool, project-named WIM-Backup, that uses the Windows Imaging Format (WIM) to create full backups of computer systems (operating system images) within WinPE and then restore them.
The application is hosted on GitHub, is open source, and is offered under the Apache 2.0 license.
In addition, the repository includes an illustrated step-by-step guide to help get it up and running.
Brief summary:
WIM-Backup always requires an external bootable media such as a USB flash drive.
From this drive WinPE is booted to perform a backup or restore to or from an external medium (e.g. a USB hard drive).
On the bootable USB flash drive the WinPE must be set up before (is documented illustrated in the readme).
After completion of the respective operation, a status message is displayed whether the operation was successful or failed.
After restoring a backup, you can boot normally from the destination drive.
Both the backup and restore process are relatively simple (not "rocket science").
To set up the solution, you need about 30 minutes time in the best case due to the necessary downloads (e .g. ADK)
Last but not least: it has a permissive license (non-proprietary) and is open source.
The project can be found here: WIM-Backup
i wrote a cuda program and i am testing it on ubuntu as a virtual machine. the reason for this is i have windows 7, i don't want to install ubuntu as a secondary operating system, and i need to use a linux operating system for testing.
my question is: will the virtual machine limit the gpu resources? So will my cuda code be faster if i run it under my primary operating system than running it on a virtual machine?
I faced a similar task once. What I ended up doing was installing Ubuntu on a 8GB thumb drive with persistent mode enabled.
That gave me 4GB to install CUDA and everything else I needed.
Having a bootable USB stick around can be very useful. I recommend reading this.
Also, this link has some very interesting material if you're looking for other distros.
Unfortunately the virtual machine simulates a graphics device and as such you won't have access to the real GPU. This is because of the way the virtualisation handles multiple VMs accessing the same device - it provides a layer in between to share the real device.
It is possible to get true access to the hardware, but only if you have the right combination of software and hardware, see the SLI Multi-OS site for details.
So you're probably out of luck with the virtualisation route - if you really can't run your app in Windows then you're limited to the following:
Unrealistic: Install Linux instead
Unrealistic: Install Linux alongside (not an option)
Boot into a live CD, you could prepare a disk image with CUDA and mount the image each time
Setup (or beg/borrow) a separate box with Linux and access it remotely
I just heard a talk at NVIDIA's GPU technology conference by a researcher named Xiaohui Cui (Oak Ridge National Laboratory). Among other things, he described accessing GPUs from Virtual machines using something called gVirtuS. He did not create gVirtuS, but described it as an opensource "virtual cuda" driver. See following link:
http://osl.uniparthenope.it/projects/gvirtus/
I have not tried gVirtuS, but sounds like it might do what you want.
As of CUDA 3.1 it's virtualization capabilities are not vivid, so the only usable approach is to run CUDA programs directly on the target HW+SW
Use rCUDA to add a virtual GPU to your VM.
I'd like to programmatically set volume in Windows, Mac and Ubuntu using C/C++. Command line also can but C/C++ preferred. Thank you in advance!
Just a hint, In windows the 'philosophy' around volume adjustment has changed between XP and Vista/7. Code that would change the master volume on XP will only change the application specific volume setting in the mixer on Vista and 7.
Here is a good blog post by one of the MS audio dev team regarding this: Larry Osterman's Blog
Here are some codeproject pages that might prove useful:
For XP
For Vista +
Also, there are a few powerpoint presentations regarding the new api's here:
AMP Summit ppts. The Audio Endpoints in Windows Vista presentation has some good info.
As for OsX and Ubuntu, i have no idea.
For Linux using ALSA sound system, you can use following command:
amixer set Master 50%
For completeness sake, here is the OSX cli version:
osascript -e "set volume output volume (output volume of (get volume settings)+2)"
And on the C side it's more difficult. From everything I found researching this, the easiest way is using one of the readily available objective C answers and wrapping them into a function in an extra object you can call from C/C++.
I'm using a barebones tutorial as the basis for an OS I'm working on, and it seems to be an older tutorial: it has be compiling the kernel down to a floppy image, and then loading it with GRUB.
Basically, I still want to use GRUB, but I'd like to have my OS run from a CD instead. The main reason is that I don't actually have a real floppy drive available (I'm testing in VirtualBox currently) and I thus have no way to test my OS on real hardware.
I've been poking around on the net, and I can find lots of utilities that create a bootable CD from a floppy image, but these all seem to require an actual floppy drive, plus it's not really what I'm looking for. I'd like to be able to end up with a bootable CD during my make step ideally, without needing to first place the image on a floppy, which seems rather pointless.
I guess the easy way to answer this: How do I set up GRUB to read my kernel image from a CD? Will I need a special utility to do this from Windows? (The kernel can't compile itself yet, that's not for a looong while)
Thanks!
I found the solution for my project on my own, with some advice from the folks over at OSdev. There is a utility called mkisofs (which can run under Windows using a cygwin dll) that takes a directory, and makes that directory into an ISO image that can be burned to a CD. Using the -b flag, you can specify which file should reside in the boot sector of the disk.
The solution is just to have GRUB in the bootsector, and use GRUB to load the kernel image, which I can compile out in non-floppy form easily.
AFAIK a bootable CD is pretty much the same as a bootable floppy. You need to put the boot loader (GRUB) into the boot sector etc., the BIOS will take care of the low level stuff until you switch to protected mode.
You will probably have to make your image and then dd it to the actual physical disk.
Here's the El Torito Bootable CD specification:
http://www.phoenix.com/NR/rdonlyres/98D3219C-9CC9-4DF5-B496-A286D893E36A/0/specscdrom.pdf
EDIT: An alternative way to test your kernel would be a bootable USB stick. Again, the BIOS will take care of the low level USB stuff until you turn on A20 and jump to protected mode.
If you're interested in looking at code, then the Moblin Image Creator is probably a good application to check out. It's written in python and can create different types of bootable images (CD, USB and NAND) for both Live and installable configurations of Moblin Linux.
I've been hearing a lot about about how the new version of VMWare Fusion can run virtual operating systems in "headless mode".
A Google search makes it clear that other virtualisation products also have similar features, however, I have not been able to find a good description of what this actually means? What is happening when you do this?
Headless mode means that the virtual machine is running in the background without any foreground elements visible (like the Vmware Fusion application)
You would have no screen to see running the front end; i.e. the screen/console would not be visible, even though the operating system is running, and would typically have to access the machine via SSH.
For anyone that is interested, you can activate headless mode in VMWare Fusion by running the following command in Terminal.app
defaults write com.vmware.fusion fluxCapacitor -bool YES