canmount=noauto fails to stop automatic mounting of root filesystem #18242
Description
System information
| Type | Version/Name |
|---|---|
| Distribution Name | OpenSUSE Tumbleweed |
| Distribution Version | 20260212 |
| Kernel Version | 6.18.9 |
| Architecture | x86_64 |
| OpenZFS Version | 2.4.0 |
Describe the problem you're observing
Root filesystem mounts automatically despite canmount=noauto.
Describe how to reproduce the problem
zpool create -O canmount=noauto zroot /dev/nvme0n1p2
automatically mounts root filesystem zroot at default mountpoint /zroot, as shown by zfs mount.
zfs umount zroot
zpool export zroot
zpool import zroot
likewise automatically mounts root filesystem zroot at default mountpoint /zroot, as shown by zfs mount.
Thus, root filesystem zroot automatically mounts when created and when importing zpool despite canmount=noauto.