Btrfs partition automatically mounted in Win10

After I turned off the secure boot, the btrfs partitions of the linux system were automatically mounted in Win 10 system. What’s the problem?

I installed F34 and Win10 on a Huawei laptop.

Do you have the windows btrfs driver installed?

No, I don’t have the windows btrfs driver installed.

I am afraid this may not be the right forum to ask a Windows-related question. There is not much you can do from Fedora side to prevent any other operating system from mounting partitions (unless you want to place your btrfs partitions inside an encrypted LUKS volume)

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I don’t know if it will work, but you could try setting the “do not automount” attribute (63) on the Linux partition. Below is a readout from my terminal showing how to get to the attribute from gdisk.

$ sudo gdisk
GPT fdisk (gdisk) version 1.0.7

Type device filename, or press <Enter> to exit: /dev/sda
Partition table scan:
  MBR: protective
  BSD: not present
  APM: not present
  GPT: present

Found valid GPT with protective MBR; using GPT.

Command (? for help): ?
b	back up GPT data to a file
c	change a partition's name
d	delete a partition
i	show detailed information on a partition
l	list known partition types
n	add a new partition
o	create a new empty GUID partition table (GPT)
p	print the partition table
q	quit without saving changes
r	recovery and transformation options (experts only)
s	sort partitions
t	change a partition's type code
v	verify disk
w	write table to disk and exit
x	extra functionality (experts only)
?	print this menu

Command (? for help): i
Partition number (1-2): 2
Partition GUID code: 4F68BCE3-E8CD-4DB1-96E7-FBCAF984B709 (Linux x86-64 root (/))
Partition unique GUID: DDC9E8AE-9AEE-4781-8A91-5413E094BE72
First sector: 2099200 (at 1.0 GiB)
Last sector: 1875384974 (at 894.3 GiB)
Partition size: 1873285775 sectors (893.3 GiB)
Attribute flags: 0000000000000000
Partition name: 'pool.a'

Command (? for help): x

Expert command (? for help): ?
a	set attributes
c	change partition GUID
d	display the sector alignment value
e	relocate backup data structures to the end of the disk
f	randomize disk and partition unique GUIDs
g	change disk GUID
h	recompute CHS values in protective/hybrid MBR
i	show detailed information on a partition
j	move the main partition table
l	set the sector alignment value
m	return to main menu
n	create a new protective MBR
o	print protective MBR data
p	print the partition table
q	quit without saving changes
r	recovery and transformation options (experts only)
s	resize partition table
t	transpose two partition table entries
u	replicate partition table on new device
v	verify disk
w	write table to disk and exit
z	zap (destroy) GPT data structures and exit
?	print this menu

Expert command (? for help): a
Partition number (1-2): 2
Known attributes are:
0: system partition
1: hide from EFI
2: legacy BIOS bootable
60: read-only
62: hidden
63: do not automount

Attribute value is 0000000000000000. Set fields are:
  No fields set

Toggle which attribute field (0-63, 64 or <Enter> to exit): 

When you say the btrfs partitions are mounted, can you actually read and modify files on those partitions while in Windows?

And just to be clear, this is a dual boot system (not Windows in a virtual machine)?

Have you installed the Windows 10 WSL sub-system, this could be an explanation for auto-mounting?

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Yes, those partitions can be read and modified. And It’s a dual boot system.

No, I didn’t install the WSL system.

Windows 10 doesn’t understand the BTRFS filesystem, unless you have an “Insiders” Windows build and Microsoft has built-in BTRFS support coming down the pipe…but that seems very unlikely. So it seems like something must have been added to Windows to give it BTRFS support.

If you open the ‘Services’ app, is there a service called ‘btrfs’ or ‘ParagonLinuxFSMounter’, or something like that?

If you just want to remove a partition showing in Windows File explorer, open the windows disk management “diskmgmt.msc” and remove the drive letter associated with that particular partition.
So this drive will not show up on your windows explorer.

you can refer this for steps - https://www.tenforums.com/tutorials/158668-how-mount-unmount-drive-volume-windows.html