Installing Windows 7 on the pure UEFI systems without CSM

Hi,

Since UefiSeven relays on VGA ROM at 0xC0000 ... It does not work on VBox EFI VMs ...

So, I have made an EFI Application that Fakes a VBE Shim/Stub for VBox EFI VMs to Run Winodws 7 SP1 / WinPE 3.1 ... By:
- Using the End of the IVT for the Shim/Stub (First Kilobyte of Physical Memory) (Allocated as EfiRuntimeServicesCode)
- The Shim/Stub Contains (VBE INFO and VBE MODE INFO) Structures and the INT10H ISR Code
- The EFI Application Places the Shim/Stub, Sets the INT10H IVT Entry, then Loads Original Windows bootx64.efi/bootmgfw.efi Using LoadImage() then StartImage()

I Tested to Boot Winodws 7 SP1 / WinPE 3.1 (UEFI, No CSM) and It "Worked" But with a Major Flaw: The Screen does Not Refresh Automatically (I Have to Minimize then Restore the VM Window Manually to Get the Fresh "Screen Image")!

Does anyone has an Idea why the Screen is Not Updating/Refreshing?

 

vbox use own fake int10
https://forums.mydigitallife.net/th...fi-class-3-devices.82137/page-29#post-1864710

 

May try to debug it with windbg to distinguish:
1. if INT10 presents
2. !devnode status (error code, resources)
3. !pci config space data (VGA arbitration enabled on upper bridge)
4. if stuck-logo happens when vgasave service disabled

 

Win7 not support pure UEFI, only UEFI+CSM with standard legacy video bios.
There is no UEFI+CSM mode in virtual machines, it is either Legacy or pure UEFI.
I have written many times that virtual machines support screen display in an unusual way - differently than real graphics cards that have GOP firmware. vbox, VMware VM do not use normal GOP, only fake int10 - go to UEFI Shell and run this command

Code:

mem c0000 112

On the right you should see Int10h (fake)

 

How this work:

VMs:

• legacy mode > legacy vbios is used
• UEFI mode > fake int10 vbios is used
• no mode UEFI + CSM

Real graphics cards on real PC:

• legacy mode > legacy vbios is used
• UEFI mode > GOP vbios is used
• UEFI+CSM mode > legacy vbios is used

 

This is interesting. Google's "AI Overview" says:

If your GPU has a UEFI GOP VBIOS, it provides the GOP driver to UEFI.
UEFI uses this driver to set up the graphics card for high-resolution display before the OS starts.
This allows you to see the UEFI interface clearly, and it's essential for modern features like secure boot.

I wonder if Google's description is technically accurate? It makes it hard to understand why a workaround such as UEFI7 or FlashbootPro is capable of working without CSM? I guess the magic is in the details, and Google's "AI Overview" isn't providing enough information.

 

They provide custom INT10 handlers when CSM disabled (commonly legacy VBIOS is not loaded, instead UEFI OptionRom is loaded), which is installed by video card's legacy VBIOS if CSM enabled. I observed several legacy VBIOS, their handlers are installed in C000 segment. In an i5-4590, I think if video card is not installed, the BIOS's INT10 (F000 segment) only provides beep function.

 

Makes sense, thanks. I was reading the words I got from google too narrowly.

 

Anyone had luck to make this run using HyperV ? I really neeed to make this as HyperV machine and no other hypervisor

I even managed to "burn" the W7 ISO (with UEFIseven) patches to an external HDD to make HyperV use the external HDD as USB drive (mounting it as being a HDD inside the VM and using it as first boot device) and booted the installer fine and I patched all files inside the VM
But when it reboots to W7 installer 2nd part (using the files on the installed HDD) it still gets stucked in the "Starting windows" black screen and nothing more
Tested with clean official ISOS, patches ISOS and even an ISO for Surface that would work fine with UEFI new hw...

Tks

Hi

Do you know how to make it work using HyperV ? Struggling here with all approaches to make it work (and exporting from Vbox or VMWare does not work since I need to make it 100% Gen 2)

I patched the installer from ISO with UEFISeven using an external HDD as boot drive and even a VHD (and X) file as being a "fake" drive and etc (and even an already patched ISO with Flashboot Pro EFI files had the same problems)

And even following all the stuff correctly no success and everytime the black screen with "Starting Windows" and no more activity from the VM

Tks

 

You'll experience it if you try running it on baytrail tablets

 

Would this help any?

https://forums.mydigitallife.net/th...from-windows-8-build-7963-to-windows-7.86144/

 

Yes if it can be successful. Very difficult. win8-dxgkrnl.sys should be ported (maybe some user mode modules should be ported as well).

 

Only way to know is to try it.