Bash on Windows 10, no loop devices

Question

I've just tried Bash on my Windows 10 PC, and it works fine. However, I found that there is no such thing as loop devices by ls /dev/, and modprobe loop gives an error output.

Does it mean this Bash doesn't support loop devices at all or is there a solution for mounting an image as a loop device?

Answer 1

Windows Subsystem for Linux 1 (WSL, formerly known as Bash on Ubuntu on Windows) did not support loop devices. There was a feature request and an issue about it on Microsoft's Git repo.

WSL 2, however, does support loop devices.

$ uname -a
Linux Blade 5.10.102.1-microsoft-standard-WSL2 #1 SMP Wed Mar 2 00:30:59 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux

$ fallocate -l 1G test.img

$ mkfs.ext3 test.img
mke2fs 1.45.5 (07-Jan-2020)
Discarding device blocks: done
Creating filesystem with 262144 4k blocks and 65536 inodes
Filesystem UUID: 549cca4d-a65f-4f4f-8428-e324feaed3d0
Superblock backups stored on blocks:
        32768, 98304, 163840, 229376

Allocating group tables: done
Writing inode tables: done
Creating journal (8192 blocks): done
Writing superblocks and filesystem accounting information: done

$ sudo mount -o loop test.img /media/

$ ls /media/
lost+found