Boot 32bit system from 64bit uefi

Has anyone ever achieved this? I've seen people doing the reverse, i.e., boot a 64bit system on a computer with a 32bit uefi. How can we go the other direction?

Edited by kelsie, 18 August 2018 - 07:26 PM.

A 32-bit system will contain a 32-bit CPU (and a 32-bit UEFI BIOS) and therefore a 32-bit CPU cannot run 64-bit software such as 64-bit UEFI boot files or a 64-bit OS.

Thanks Steve. The CPU is 64bit and I suppose its uefi is 64bit as well because bootia32.efi is ignored. The challenge is to boot a 32bit operating system from it.

Edited by kelsie, 18 August 2018 - 07:35 PM.

Well you could MBR-boot to clover 32-bit and then boot from a 32-bit UEFI .EFI boot file.

 

The problem with UEFI is that 32-bit UEFI is in a different CPU mode from 64-bit UEFI.

 

I didn't think it was possible unless you use a 'fake' UEFI BIOS like Clover? 

If you are wanting to do this with windows, it cannot be done.  x86 uefi is reserved for chip-on-board devices, and cannot be booted with an x64 cpu, even though x64 cpus will run x86, when it comes to uefi the bootloader has to match the architecture, and this could just be limited to windows.  I suppose if you diassembled bootx64.efi and modified the bits properly it could be done.  not really worth the trouble.

 

if you are wanting to do this with linux, I think it is possible.  https://medium.com/@...es-d39b1d1961ec

I probably should have said that the goal is to boot something that is not 64-bit, whichever way, as long as it starts with the computer 64-bit uefi, because I can't change that.

 

stayboogy, as far as I could tell, that article is for 32-bit uefi --> 64-bit os. This is for the opposite direction: 64-bit uefi --> not 64-bit os.

 

Can clover be activated by uefi?

Usual hairy reasoner questions  :
 
Is this a theoretical discussion?
or do you actually have:
1) a real, existing, 64 bit system (hardware)
2) a real, existing, 32 bit operating system (software)
and you want to boot #2 on #1?
 
If the latter applies, post some actual info on hardware and software, a specific solution might be easier to find than a "universal" one, or, viceversa, a given hardware/OS combo might result being impossible with available tools.
 
Loosely (theory):
1) the built-in firmware (UEFI) must have BIOS compatibility mode (Legacy or CSM, etc.)
2) you boot in BIOS *something*, *like* grub4dos (which is BIOS only), see:
https://www.rmprepus...m/tutorials/122
3) from grub4dos you chainload Clover (either 32 bit ot 64 bit)
4) from Clover you either chainload bootia32.efi or bootx64.efi or whatever file your OS has
5) see what happens
 

Wonko

Ha, no not theoretical, still have some joy in organic life. The computer is an hp desktop, came with windows 7, has legacy mode but bios is locked on uefi mode, hence the question. The software could be anything really, as long as is not 64-bit.

The computer is an hp desktop, came with windows 7, has legacy mode but bios is locked on uefi mode, hence the question.

Post the EXACT model.

What exactly do you mean as "locked on UEFI"?
Is it an issue to access the firmware setting as in "locked by HP on all PC's of this particular model" or is it a special case (forgotten admin password or similar)?
Maybe there is a BIOS mod or something.


Wonko

Yes, and I don't have the password to change it. It's an hp eliteone.

Yes, and I don't have the password to change it. It's an hp eliteone.

 

There must be something strange in the meaning of EXACT that somehow I fail to convey.

 

Anyway, for the EliteOne G1:

https://www.manualsl...page=202#manual

 

 

 

Resetting the setup and power-on password
To disable the power-on or setup password features, or to clear the power-on or setup passwords,complete the following steps:
1.Shut down the operating system properly, then turn off the computer and any external devices,and disconnect the power cord from the power outlet.
2.With the power cord disconnected, press the power button again to drain the system of anyresidual power.
WARNING!To reduce the risk of personal injury from electrical shock and/or hot surfaces, besure to disconnect the power cord from the wall outlet, and allow the internal system componentsto cool before touching.
CAUTION:the system board even when the unit is turned off. Failure to disconnect the power cord can resultin damage to the system.Static electricity can damage the electronic components of the computer or optional equipment.Before beginning these procedures, ensure that you are discharged of static electricity by brieflytouching a grounded metal object. See the Regulatory, Safety and Environmental Notices guidefor more information.
3.Remove the access panel.
4.Locate the header and jumper labeled PSWD.
NOTE:The password jumper is blue so that it can be easily identified. For assistance locating the password jumper and other system board components, see the Illustrated Parts & Service Map(IPSM). The IPSM can be downloaded from http://www.hp.com/support
5.Remove the jumper
6.Replace the jumper.
7.Replace the access panel.
8.Reconnect the external equipment.
9.Plug in the computer and turn on power. Allow the operating system to start. This clears the currentpasswords and disables the password features.
10.Establish the new passwords in Computer Setup. SeeComputer Setup (F10) Utility on page 105 for information.

 

Wonko

Thanks for that Wonko. I didn't realize why you were asking for the model otherwise I would have said earlier that the computer is not mine and I can't make those sort of modifications. I only come to reboot when the obstacle is really convoluted.

Thanks for that Wonko. I didn't realize why you were asking for the model otherwise I would have said earlier that the computer is not mine and I can't make those sort of modifications. I only come to reboot when the obstacle is really convoluted.

 

Really I don't get it. 

 

If the computer is not yours, but you have legal use of it, *someone* must have set that limitation/password on the BIOS/UEFI.

Let's say for the sake of reasoning, the IT guy/gal in your office.

Maybe - just maybe - he/she is,  exceptionally, NOT a mindless authoritarian troll[1], and the limitation has been set EXACTLY because there are some reasons to prevent that PC from booting *anything* else but the supplied installed Windows 7.

If this (or similar) is the case, then the problem becomes more "how to boot a 32 bit system on 64 bit UEFI without being caught or leaving behind evidence of mingling with the BIOS/UEFI", which is a much more complex one - even set aside the moral or legal implications.

 

Now, booting a 32 bit system on a 64 bit UEFI - set aside the sheer fun of it  - cannot possibly be your final goal, once the *whatever* 32 bit system will be booted, you plan to do something with it.

 

Maybe this final goal can be achieved without booting a 32 bit system on a locked to UEFI 64 bit system?

 

JFYI, and only to hopefully avoid falling into the XYZ problem:

https://jdebp.eu/FGA...red-banana.html

maybe you want to tell us what this final goal is?

 

Wonko

 

 

 

 

 

[1] as most IT guys/gals often are, sometimes with a reason sometimes only because they are bastards at heart

So you can tell us what you actually want to boot to?

 

Also, is Secure Boot enabled?

The goal is to run a 32bit application so the exact os is secondary. May be windows, dos, linux... Secure Boot is not enabled.

OK, so the goal is not to UEFI-32 boot at all, but to boot to any OS and then run a 32-bit application.

Well why not UEFI-64 boot to Win10PESE 64-bit which has WoW64 and then you can run a 32-bit Windows application?

Yes, as Steve said, Windows 64 bit can run any 32 app - UNLESS the app you want to run is specifically designed to NOT run in a 64 bit OS.  I'm afraid I've run into a few of these and it usually is the result of the apps author specifically testing for a 64 bit OS and refusing to run.  In the case of the apps I've found it was to force the user to buy a separate 64 bit version of the app. There was no reason whatsoever that the app couldn't run on a 64 bit OS.  Thankfully these are far and few between.

OK, so the goal is not to UEFI-32 boot at all, but to boot to any OS and then run a 32-bit application.

Well why not UEFI-64 boot to Win10PESE 64-bit which has WoW64 and then you can run a 32-bit Windows application?

Well, why then not plainly run the 32 bit mysterious[1] application in the existing, installed, Windows 7 (that surely has WOW64 included)?

 

Wonko

 

[1] I cannot but call mysterious an application for which the OS is secondary (windows, dos, linux) . 

If you want to run 32-bit linux (and 32-bit apps) from a UEFI64 boot, then just boot to Clonezilla.

It has 32-bit and 64-bit UEFI .EFI boot files for grub2 but the same 32-bit kernel is loaded.

P.S. Same for linuxmint 32-bit. You can UEFI boot to grub2 and then boot from the ISO