Windows 10 1909 Recovery Partition Behavior with Ubuntu installed

[ChrisAllover]

For the Microsoft Team at HP:

I loaded Ubuntu as a backup OS using the proper tools so that it is in the Secure Boot (EFI) Partition, and can be selected from the UEFI boot menu (Bios). It is hidden from Windows bootfile (I did not add it to bcd).

When the installer ran under default Ubuntu, during the partition (GParted) setup, the installer could only "see" the "C" drive as a viable partition for shrinking to allow room for Ubuntu. I gave it 240GB (est.) to use, then it installed the OS, rebooted, and all was well.

The Ubuntu MOKUTIL worked with Secure Boot and fTPM flawlessly. It was a learning curve to use, but so is Windows these days.

Here's the question: If the WinRE partition created during factory install (Not the hidden HP partition, the one Windows 1909 created) (holds the windows.wim file for recovery) of Windows (On this machine it is at the end of the drive space, about 487MB) needs more space, according to Windows, the partition is dynamic for space, and grows its own needed space by reaching forward (since it is at the end of the drive space) rather than back. Since I placed Ubuntu at the end of "C" so to speak, and made sure that the GParted utility did not show Diskpart any partition information or drive letter, (Disk Management sees it as a healthy unnumbered partition between "C" and the recovery partition) will the WinRE created recovery partition "skip" over the ext4 formatted partition (Ubuntu) and get more space from the actual "C" drive if needed, or will Windows 10 start acting up in the drivespace world (throw errors, start reformatting "unknown partitions", etc. ?

If you don't know right now, that's OK, I have time to test here and will see if Windows 10 or Ubuntu starts acting up in the drive space. So far, only thing that I had to reset was the drive counters in Windows through error checking. That went well and picked up new partition (ext4) in Disk Management. I will be glad when Windows starts seeing other partitions types (at least see them for their type. Maybe one day).

Please don't tell me to restore my computer. I have been around these since the 1980's, starting with DOS/CPM 1,0 with an HP SCSI 8-bit Motorola Processor, so BE GENTILE with your replies!

[WAWood]

@ChrisAllover 

Appreciate your comments, but we are not 'the Microsoft Team at HP".  Instead, we are mostly a bunch of volunteers helping folks with HP system problems as best we can.

That's an interesting comment about the WinRE recovery partition growing.  I did not know that.  As, I've had Win10 on PCs here since the earliest days of the Windows Insider functions and have not seen that, myself.

As to reaching around to grab more disk space, I would doubt that -- but you never really know what MS can do behind the scenes as they are not likely to tell us about that.

Have you gone back into Windows to confirm it still works?Asking because the Linux installer, in all too many cases, causes Windows filesystem corruption when it shrinks an OS partition to make room to install itself.  I have always used the "something else" option to avoid that problem.

[ChrisAllover]

Hey, thank you for the heads up on where to submit this. Yes, I read the Microsoft Technical Documents for the OEM setup files when they initially load a new PC with version 1909 (does not apply to earlier version upgrades to 1909 just brand new loading of 1909). And you are correct on the partition reading corruption between the two systems. Windows sees an ext4 or whatever partition used on Linux as a problem, so Disk Manager in windows complains about the new partitions, but all it takes to make it happy is to let it run its repair tool to pin down the arrangement and it will be happy (I think it just wants to know where all of its files went to, and to make sure all the boot files are pristine). Funny how Linux GParted never complains, just update the tables and run the OS. That is, if you did your partition by the rules. If not, well, I find the hp logo looks better facing away from the door on the floor!

Chris   P.S. I'll send a DM to Microsoft (God help us all) when this is over and see what they recommend (I know I can fix whatever they want done, more than likely grow the recovery partition (very delicate operation, and requires reboot)

[ChrisAllover · Accepted solution]

Conclusion for Record

Kept seeing weird errors about Ubuntu 18.04 LTS not properly using the fTPM device and  it was disabling it through the UEFI BIOS. It was seeing the security keys from MS and was not able to use them, so it just turned off the fTPM and used the Secure Boot to load the OS while in "normal" UEFI/GPT boot (Not Legacy).

In addition, due to recent changes at MS with the Windows OS and Storage Sense as a application, there were problems with Windows 10 1909 not "seeing" the ext4 Linux partition (And Disk Manager in Windows only had One option allowed to manage the  Linux Partition was to delete the ext4  and allow the "C" drive full access the the drive. (So that it could use the trailing Reserved Partition which was set to grow forward dynamically and use the additional "C" drive space if needed for updates and revisions).

Since all of this was setup initially during the OEM factory install, it is nearly impossible to make any changes to the system that would not effect the entire system, and by association, both OS's ability to work.

Lesson to the community: If you want Linux and Windows on new system, better order it from the factory built that way. They are the only ones with the tools and access to setup the features each OS needs to run properly.  Aside from the fact that the fTPM has a very LOW tolerance for changes, and could end up being corrupted beyond repair if you are not careful with the security hardware/firmware.

My advice would be (if you really need to use Ubuntu as an available OS) upgrade Windows 10 to Pro, then add the VM machine properties in system, then load Ubuntu as a VM under Windows Pro.

That way, the Security Hardware will only be handling one OS at a time, and the risk of you losing all your data from Security related corruptions should be very low. Just a suggestion. You can do as you want and feel comfortable with, but a least you'll know what I ran across in the process.