Crash during manual partitioning: ValueError: Mountpoint is not specified due to leftover BTRFS subvolumes with None paths.

[ts1p0k]

Which ISO version are you using?

2026-02-26

The installation log

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describe the problem

When attempting to install Arch Linux using archinstall on a disk that contains a leftover BTRFS partition from a previous failed installation, the installer crashes with a ValueError: Mountpoint is not specified in _mount_btrfs_subvol.
​This crash occurs even if Wipe: True is explicitly selected for that partition in the manual partitioning menu. It appears that the installer attempts to read and parse the existing broken BTRFS subvolumes (which show up with None as their path/mountpoint in the menu) before performing the actual wipe/format operation. Since it doesn't know how to mount a subvolume with a None path, it throws an exception and aborts the installation entirely

Exiting archinstall and manually running wipefs -a /dev/nvme0n1pX on the problematic partition completely removes the leftover subvolumes. After doing this, running archinstall again and configuring the partition works perfectly. The installer should ideally ignore or wipe these invalid subvolumes automatically when Wipe: True is flagged.

​Hardware / Environment:
​Device: Laptop
​CPU: AMD Ryzen 5 4600H
​GPU: NVIDIA GTX 1650
​RAM: 16GB DDR4 3200MHz
​Setup: Dual boot with Windows on a single NVMe drive.Exiting archinstall and manually running wipefs -a /dev/nvme0n1pX on the problematic partition completely removes the leftover subvolumes. After doing this, running archinstall again and configuring the partition works perfectly. The installer should ideally ignore or wipe these invalid subvolumes automatically when Wipe: True is flagged.

​Hardware / Environment:
​Device: Laptop
​CPU: AMD Ryzen 5 4600H
​GPU: NVIDIA GTX 1650
​RAM: 16GB DDR4 3200MHz
​Setup: Dual boot with Windows on a single NVMe drive.