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UEFI Windows 8 + BIOS Grub4dos = MultiBoot USB-Harddisk

uefi win8 linux bios grub4dos vhd win7 xp multiboot usb

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#1 wimb

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Posted 12 December 2012 - 07:03 AM

Go direct to new description including Windows 10 

http://www.msfn.org/...-2#entry1117324

 

 
=========================================================================================

 

UEFI Windows 8 + BIOS Grub4dos = MultiBoot USB-Harddisk

Everything At Once


Windows 8 came on computer with UEFI firmware and GPT partitioning of the internal harddisk.
On trying to boot with my existing USB-harddisk Or CD / DVD then initially Everything Failed.
UEFI does not like Grub4dos and so all boot Images failed. The boot CD's were not compatible with UEFI.

It was time to redesign USB Multiboot.

On computer with UEFI firmware I can Install Windows 8 on normal USB-harddisk having MBR and three primary partitions.
The first Boot partition E: is FAT32 Win8 Format and contains the EFI folder
and the second partition M: is NTFS with Windows 8 System Installed by using WinNTSetup2.
GPT partitioning is not needed and unwanted because it would only boot on UEFI firmware.

Install of Win 8 on USB using UEFI computer and latest beta version of WinNTSetup2 is OK smile.gif
Did not use any other tool. Boot and EFI folder are created on FAT32 Boot partition.
http://www.msfn.org/...winntsetup-v23/

 

UEFI_MULTI.exe is program to make Multi-Boot USB-Harddisk to boot computers having BIOS or UEFI firmware
Follow Tutorial UEFI MULTI - http://reboot.pro/to...182-uefi-multi/ and http://www.911cd.net...showtopic=25269

 

=======================================================================================================

Manual procedure using Windows 8 Tools to make USB-harddisk bootable on BIOS Or UEFI computer:
Use Win 8 tools bootsect.exe to reset MBR bootcode and FAT32 PBR according to Win8
and use bcdboot.exe to create the Boot and EFI folder for booting Windows 8 from FAT32 partition.

 

bootsect.exe /nt60 E: /force /mbr

 

bcdboot.exe M:\Windows /s E: /f ALL

 

bcdedit.exe can be used to add Grub4dos entry in Boot\BCD for booting ISO and VHD Image files on BIOS computers.

http://diddy.boot-la...ws.htm#windows3

 

=======================================================================================================

 

Now I can boot from USB-harddisk on BIOS and on UEFI computers with Win8 (flat)
and with Grub4dos using all kind of Image files (Linux Parted Magic + LiveXP + 7PE + Portable XP + Win7)

Some Mobo e.g. Gigabyte GA-Z77MX-D3H allow to use F12 Boot Menu
and Select either BIOS or UEFI booting from USB-harddisk.

In my case BIOS Grub4dos booting Image files on UEFI computer is only possible
after switching in UEFI the Advanced OS setting from Win8 to Win7 / Other
For booting Windows 8 then the UEFI Advanced OS setting Win8 is used.

So now really Everything At Once is working.


Attached File  7PE_x64.png   110.82KB   223 downloads = Attached File  Win7-UN.png   287.3KB   242 downloads = Attached File  LXP_WIM.png   303.74KB   190 downloads


http://www.youtube.c...h?v=ZZ2cftjyHys


More Info on Universal PE http://reboot.pro/to...pe/#entry166561

:cheers:


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#2 Sha0

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Posted 12 December 2012 - 07:31 AM

If the computer does not support BIOS emulation, then you cannot use MBRs nor GRUB4DOS, as there will be no INT 0x13.  Fortunately, you don't have such a computer.  Cool stuff!



#3 wimb

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Posted 14 December 2012 - 11:56 AM

It might quite well be that Win8 can be installed this way on USB for any UEFI computer.

Booting Grub4dos on UEFI computer is a different story.
In that case you really need to have the option to switch in UEFI the Advanced OS Setting from Win8 into Win7 / Other.
UEFI Setting Win8 boots via EFI folder and Grub4dos does not work
UEFI Setting Win7 / Other boots via Boot folder and Grub4dos works on UEFI computer
The Win7 / Other Setiing in UEFI might be called "BIOS compatible"

Now that UEFI computer can boot Windows 8 from USB-harddisk with EFI folder in FAT32 partition and Standard Win8 MBR,
it would be interesting to get more feeling on how actually the bootsequence is working.

I may be wrong but it feels like:

UEFI > MBR bootcode > parttion table > FAT32 bootsector > EFI\Boot\bootx64.efi > EFI\Microsoft\Boot\bootmgr.efi reads BCD > bootmgfw.efi

EFI\Microsoft\Boot\BCD OS entry > NTFS partition > \Windows\system32\winload.efi

I feel a bit confused about the files bootmgr.efi and bootmgfw.efi in folder EFI\Microsoft\Boot

Can you give more explanation ?


Some more Screenshots for booting Windows 8 from USB and for Image Files on USB via Grub4dos using UEFI Computer

Windows 8 on USB = Parted Magic ISO = Win7-x64.vhd = Portable XP-1-P.vhd

 

Attached File  Win8-USB-2012-12-14_114035.png   496.29KB   69 downloads  =  Attached File  PartedMagic-W8.png   476.09KB   72 downloads  =  Attached File  Win7-x64-VHD-W8-2012-12-14_111253.png   467.75KB   52 downloads  =  Attached File  XP-2-P-VHD-W8-2012-12-14_105147.png   589KB   39 downloads


:cheers:

 



#4 steve6375

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Posted 14 December 2012 - 02:03 PM

So can you take your nice multiboot hard disk and connect it to a different UEFI-enabled computer (one which you have not run bcdboot /UEFI on before) and do a UEFI boot from it?

Doesn't the bcdboot /UEFI command actually write into the BIOS NVRAM the name of the initial UEFI boot file?



#5 wimb

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Posted 14 December 2012 - 03:10 PM

I can boot from USB-harddisk with Windows 8 on my UEFI computer and on my BIOS computers.
This config is brand new and I have here no other UEFI computer available to test if it works on a different UEFI computer.
I guess that the initial UEFI bootfile is always defined as EFI\Boot\bootx64.efi

May be you have more models available and can test the idea.

I have here some interesting screenshots of the first 4 sectors of the GPT partioned Internal harddisk of my computer
to study how EFI booting works. Here is what I think (but I might be wrong ...)
Sector 0 has some partition table indicating Unknown Partition type EE beginning at sector 2
Sector 1 defines it as EFI PART (info)
Sector 2 and 3 is the GPT partition table

Attached File  Sector0-x2012-12-14_141927.png   740.79KB   33 downloads = Attached File  2012-12-14_142815.png   745.88KB   45 downloads = Attached File  2012-12-14_142842.png   781.96KB   33 downloads = Attached File  2012-12-14_143957.png   764.36KB   23 downloads

#6 Sha0

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Posted 14 December 2012 - 06:53 PM

I may be wrong but it feels like:

UEFI > MBR bootcode > parttion table > FAT32 bootsector > EFI\Boot\bootx64.efi > EFI\Microsoft\Boot\bootmgr.efi reads BCD > bootmgfw.efi

EFI\Microsoft\Boot\BCD OS entry > NTFS partition > \Windows\system32\winload.efi

I feel a bit confused about the files bootmgr.efi and bootmgfw.efi in folder EFI\Microsoft\Boot

Can you give more explanation ?
Sure. You are close, but bootmgfw.efi and bootmgr.efi are not quite right. There are a few (at least 4) different kinds of BootMgr. Then BootMgFw.efi adds two (x86 & x64) more to that, for a total of 6.

BootMgFw is a (U)EFI application and is expected to be invoked directly by the (U)EFI firmware. The other BootMgr flavour is not.

So on a PC/AT system, you'd have: BIOS -> MBR -> VBR -> BootMgr (which is real-mode stub -> embedded BootMgr.exe) -> BCD on active partition

On an (U)EFI system, you'd have: (U)EFI Firmware -> BootMgFw.efi (loaded from EFI "firmware partition" on your GPT disk) -> BCD on EFI "firmware partition"

The file extensions are confusing. For example, memtest.exe and memtest.efi are really the same thing.

All of this knowledge can be gleaned from Microsoft's published symbol files and from debugging with WinDbg. I am not 100% sure when BootMgr.efi is usually used in practice, but I believe that it can be chained-to from BootMgFw (untested). It might be so that the EFI BCD can be distinct from a separate BCD, but I don't know, yet.

So can you take your nice multiboot hard disk and connect it to a different UEFI-enabled computer (one which you have not run bcdboot /UEFI on before) and do a UEFI boot from it?
Unfortunately, there is a pretty big fundamental problem that I learned about recently from some IRC discussion in the #syslinux channel:
  • Some BIOSes will refuse to boot a disk that does not have an active partition in the MBR partition table.
  • Some EFI firmware will refuse to boot a disk that does have an active partition in the MBR partition table.
Unfortunately, this means that it is impossible to have a disk that will be truly universal and that will satisfy both of these "jerks."

Doesn't the bcdboot /UEFI command actually write into the BIOS NVRAM the name of the initial UEFI boot file?
As far as I know, yes, unless you additionally tell it not to with /s.

#7 steve6375

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Posted 14 December 2012 - 07:00 PM

The bcdboot command line spec mentions...

 

 

By default, BCDboot creates a Windows Boot Manager entry in the NVRAM on the firmware to identify the boot files on the system partition. If the /s option is used, then this entry is not created. Instead, BCDboot relies on the default firmware settings to identify the boot files on the system partition. By the UEFI 2.3.1 spec, the default firmware settings should open the file: \efi\boot\bootx64.efi in the EFI System Partition (ESP).


#8 Sha0

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Posted 14 December 2012 - 07:04 PM

In fact, if someone has a 32-bit Windows 7, I'd appreciate it if they could search it for all BootMg* files and report what's there. It might be the case that Microsoft is simply using the .efi extension for x64 systems, but I haven't thought about this thoroughly and have no idea what's on a 32-bit Windows 7 installation disc.

#9 Sha0

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Posted 14 December 2012 - 07:06 PM

The bcdboot command line spec mentions...
Did you mention that independently of my response to your previous post, or are you perceiving an inconsistency somewhere?
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#10 Wonko the Sane

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Posted 14 December 2012 - 07:18 PM

Maybe useful, maybe not :unsure:

http://gitorious.org...I_booting_works

http://gitorious.org...64_BIOS_to_UEFI

 

:cheers:

Wonko



#11 Sha0

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Posted 14 December 2012 - 07:40 PM

Maybe useful, maybe not :unsure:
http://gitorious.org...I_booting_works
http://gitorious.org...64_BIOS_to_UEFI
If that second article's initial notes are correct, then that lessens the number of combinations that actually exist on actual installation media in the world. That "smells right," but doesn't exactly help to explain the x64 bootmgr.efi, unless I've missed something.

#12 cdob

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Posted 14 December 2012 - 09:55 PM

I may be wrong but it feels like:
UEFI > MBR bootcode > parttion table > FAT32 bootsector > EFI\Boot\bootx64.efi > EFI\Microsoft\Boot\bootmgr.efi reads BCD > bootmgfw.efi

 

http://www.uefi.org/
UEFI_Specification_2_and_Errata_Sept16_08.pdf

2.6.2 Platform-Specific Elements
In addition, partition support for MBR, GPT, and El Torito must be implemented.

12.2 File System Format
EFI encompasses the use of FAT32 for a system partition, and FAT12 or FAT16 for removable
media.

3.4.1.1 Removable Media Boot Behavior
... a default file name in the form \EFI\BOOT\BOOT{machine type short-name}.EFI.
Table 9
32-bit BOOTIA32.EFI
x64 BOOTx64.EFI

 

If there is no EFI system partition, then a MBR is supported.
There is partition table involved, but no MBR boot code or partition boot code.
UEFI reads a file name \EFI\Boot\bootx64.efi



#13 Sha0

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Posted 14 December 2012 - 10:32 PM

http://www.uefi.org/
UEFI_Specification_2_and_Errata_Sept16_08.pdf
 
If there is no EFI system partition, then a MBR is supported.
There is partition table involved, but no MBR boot code or partition boot code.
And there is still the trouble:

  • Some BIOSes will refuse to boot a disk that does not have an active partition in the MBR partition table.
  • Some EFI firmware will refuse to boot a disk that does have an active partition in the MBR partition table.
Unfortunately, this means that it is impossible to have a disk that will be truly universal and that will satisfy both of these "jerks."
 


 
UEFI reads a file name \EFI\Boot\bootx64.efi
Only by default (without an NVRAM EFI_LOAD_OPTION override) and only for an x64 architecture. The other architectures have BOOTIA64.EFI, BOOTIA32.EFI, BOOTARM.EFI. BootMgFw.efi can be renamed to BOOTX64.EFI to avoid using the NVRAM, for x64.

#14 wimb

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Posted 15 December 2012 - 07:41 AM

http://www.uefi.org/
UEFI_Specification_2_and_Errata_Sept16_08.pdf

 

If there is no EFI system partition, then a MBR is supported.
There is partition table involved, but no MBR boot code or partition boot code.
UEFI reads a file name \EFI\Boot\bootx64.efi

 

Thanks for all useful info on UEFI
MBR is supported means that the configuration of my MultiBoot USB-harddisk is conform the UEFI specification.

The initial UEFI loader is file EFI\Boot\bootx64.efi as defined by UEFI specification.

 

The file bootmgfw.efi is mentioned in the BCD store used for UEFI booting.

bootmgfw.efi is equal to bootx64.efi and differs only by name

I did not know or do anything with NVRAM but apparently launching bootmgfw.efi

as made in E:\EFI\Microsoft\Boot\BCD  by bcdboot.exe

avoids using NVRAM as mentioned by Sha0
 

bcdedit /store E:\EFI\Microsoft\Boot\BCD /enum


has in Windows Boot Manager section
 

path       \EFI\Microsoft\Boot\bootmgfw.efi

 

Here is the final complete listing of Boot\BCD used for BIOS booting after adding entries for the Win7 VHD's and adding Grub4dos as default entry

and the listing of EFI\Microsoft\Boot\BCD used for UEFI booting

 

UEFI booting of Win7-x64.vhd did NOT work for me (signature security problems)

BIOS booting of Win7-x64.vhd and booting Image files with Grub4dos works OK.

 

UEFI and BIOS booting of Windows 8 from USB is working OK

 

Attached File  bcd_w8_usb.txt   4.31KB   76 downloads  and  Attached File  menu_lst.txt   2.96KB   58 downloads

 

:cheers:



#15 wimb

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Posted 16 December 2012 - 07:37 AM

There is NO active partition entry in the protective MBR of the internal GPT harddisk.

The entry in the partition table refers to EE partition beginning at sector 2 where the GPT partition table is located.

 

I think that for a GPT harddisk then UEFI refuses active partition in MBR.

 

Quite different is my case where standard MBR and partition table is used

that is allowed according to UEFI specification when no EFI partition is found.

In that case the partition table in the standard MBR must have first the FAT32 partition set active

used as bootpartition for UEFI followed by the NTFS System partition.



#16 Sha0

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Posted 16 December 2012 - 09:26 AM

Although I've posted it twice, perhaps there is still a misunderstanding, or possibly disbelief?
Unfortunately, there is a pretty big fundamental problem that I learned about recently from some IRC discussion in the #syslinux channel:
  • Some BIOSes will refuse to boot a disk that does not have an active partition in the MBR partition table.
  • Some EFI firmware will refuse to boot a disk that does have an active partition in the MBR partition table.
Unfortunately, this means that it is impossible to have a disk that will be truly universal and that will satisfy both of these "jerks."




#17 wimb

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Posted 16 December 2012 - 09:39 AM

Although I've posted it twice, perhaps there is still a misunderstanding, or possibly disbelief?

 

Standard MBR with active FAT32 boot partition and NTFS system partition

is allowed according to UEFI specification when no EFI partition is found.

 

My MultiBoot USB-harddisk is build according to this scheme and is booting perfect on UEFI computer in UEFI mode.

 

My "belief" or better "understanding" is based on experimental evidence and on the UEFI specification.



#18 cdob

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Posted 16 December 2012 - 01:08 PM

My "belief" or better "understanding" is based on experimental evidence and on the UEFI specification.

 

UEFI specification is vague at removable media MBR matter.

Is Partition type importand? is partition table layout importand?

Does UEFI search all parition table entries? Is the first entry importand only?

Is the active partition imortand?

What's the first partition table entry? What's the fourth partition table entry?

Imagine a first NTFS partition table entry and a second active FAT partition table entry.

 

Different UEFI firmware may give different results

All tests relate to the used hardware. 

 

@shao and wimb

Can you name some hardware results?



#19 wimb

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Posted 16 December 2012 - 01:28 PM

@shao and wimb
Can you name some hardware results?

Sure we need more results for booting MBR harddisks on UEFI computers,
but the present results are quite promising and are according to UEFI specification.

My UEFI computer hardware is:
Medion Akoya P5220D = MD8816 with Intel Quad Core i5-3350P 3.1 GHz Ivy Bridge processor
more details see Pictures in previous posts

 

UEFI BIOS

Medion 1111 2011

M7797W08.20C

American Megatrends - 4028D

My USB-Harddisks tested for booting Windows 8 and all VHD and ISO images on BIOS and UEFI OK are:
- Samsung Portable S2 320 GB - win8 MBR - 20 GB Active FAT32 Win8 format - 40 GB NTFS System partition
- WD Elements Portable 320 GB - same config

 

Also tested on  Mobo Gigabyte GA-Z77MX-D3H that allows to use F12 Boot Menu

and Select direct either BIOS or UEFI booting from USB-harddisk.

 

In all cases standard MBR USB-harddisk with Active F32 boot partition having Boot and EFI folder

is working OK for booting BIOS Grub4dos Image files and UEFI Windows 8 (flat).

:cheers:



#20 Wonko the Sane

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Posted 16 December 2012 - 01:33 PM

My "belief" or better "understanding" is based on experimental evidence and on the UEFI specification.

 

I guess that what Sha0 is trying to tell you (and at least this is what I am personally trying to tell you) is that your evidence is valid :thumbsup:, but most probably it doesn't apply "generically" to every hardware and/or UEFI/EFI/BIOS/whatever existing implementation.

 

I suspect that we are in a situation not very different from the - by now largely solved ;) - USB booting issues where different hardware and BIOS, and partitioning scheme, and geometry and size and device seen as fixed vs. removable, and actual filesystem used and actual MBR code and what not can make a dramatic difference such as booting vs. NOT booting.

 

In other words, I see your results as a great achievement :), but I consider them not a point of arrival, but  rather a brand new starting point, which allows me to be optimistic about possible greater and wider achievements in the future:

http://reboot.pro/to...rthday/?p=15859

 

If you prefer, we all agree that more tests on more "assorted" hardware are needed before declaring this as a "one size fits all solution", or if you want a grumpy statement ;), you are currently mis-representing :w00t: your approach as "universal" while there is not any evidence of it being so. :ph34r:

 

 

:cheers:

Wonko 



#21 wimb

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Posted 16 December 2012 - 01:44 PM

Sure, we need more results for booting MBR USB-harddisks on UEFI computers.

But the present results are quite promising and the UEFI specifications in fact predict that it will work on most (all well designed) UEFI computers.

It makes me optimistic that it might be the Universal Solution that we need in the future to boot from USB on all types of computer.

:cheers:

#22 wimb

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Posted 16 December 2012 - 02:49 PM

The UEFI Specification describes in detail in Section 5.2.1 how MBR is supported.

 

The MBR Bootcode is not executed by UEFI firmware and the BootIndicator field (value 0x80) is not used by UEFI firmware.

 

Attached File  UEFI_Spec2012-12-16_155832.png   646.16KB   25 downloads

 

:cheers:



#23 Wonko the Sane

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Posted 16 December 2012 - 05:14 PM

Again, I don't want you to talk you down or anything negative, rest assured :), but besides standards, there is also the way engineers and programmers read them and the way they actually test compliance to them.

 

To give you an unrelated example, the ISO 9660 or El-Torito standard or ECMA-119 are there since 1987/1988, still it took several years, some accurate reading, some field experiments, and a nice bit of lateral thinking by Rudolph Loew :worship: (and some  - moderate ;) - form of "torture" :ph34r:  applied to him by yours truly :smiling9:) to prove how most BIOS programmers had read them "wrongly" for all these years, or did not apply them fully , see:

http://www.msfn.org/...oppy-emulation/

http://www.msfn.org/...post__p__972183

 

in this case the "mis-reading" had trifling consequences, in the sense that all what happened was that every single programmer in the world self-limited their software to a sub-set of the possibilities without preventing the "base" working of floppy emulation as boot media, but still I can imagine tens if not hundred of cases in which a larger floppy image available for boot CD's would have made a whole lot of difference. 

 

:cheers:

Wonko

 



#24 wimb

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Posted 16 December 2012 - 06:01 PM

Sure, we need more results for booting MBR USB-harddisks on UEFI computers.

We need more results ....

#25 Sha0

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Posted 16 December 2012 - 10:44 PM

We need more results ....
What partition type code byte are you using for your FAT partition, in the MBR?

UEFI 2.3 has 3.4.1 Boot via the Simple File Protocol, which includes:
...
The format of the file system specified is contained in Section 12.3...


Then 12.3 File System Format includes:
...To differentiate the EFI file system from pure FAT, a new partition file system type has been defined.

...The FAT32 system partition is identified by an OSType value other than that used to identify previous versions of FAT. This unique partition type distinguishes an EFI defined file system from a normal FAT file system.

Then 12.3.3 Number and Location of System Partitions includes:
...
Software installation may choose to create and locate an ESP on each target OS boot disk, or may choose to create a single ESP independent of the location of OS boot disks and OS partitions. It is outside of the scope of this specification to attempt to coordinate the specification of size and location of an ESP that can be shared by multiple OS or Diagnostics installations...


Then 5.2.1 Legacy Master Boot Record (MBR) (which you already referred to) includes:
...
...The operating system indicator value of 0xEF defines a partition that contains a UEFI file system. The other values of the system indicator are not defined by this specification. If an MBR partition has an operating system indicator value of 0xEF, then the firmware must add the EFI System Partition GUID to the handle for the MBR partition using InstallProtocolInterface(). This will allow drivers and applications, including OS loaders, to easily search for handles that represent EFI System Partitions.

So I'd suggest that you use 0xEF.

Also: Please test an HP EliteBook and a ThinkPad with your universal UEFI-/BIOS-bootable USB storage device, if you ever have the chance.





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