Re: [gentoo-user] Can't create valid btrfs on NVMe

["J. Roeleveld" <joost@antarean.org>]

On Wednesday, August 17, 2016 11:26:13 PM Neil Bothwick wrote:
> I'm putting together a new desktop using a Samsung SM951 NVMe drive. I
> booted sysrescd, partitioned the drive and ran
> 
> mkfs.btrfs /dev/nvme0n1p3
> mount /dev/nvme0n1p3 /mnt/custom
> 
> df -T, mount and findmnt all show this is mounted as a btrfs filesystem,
> e.g.
> 
> /dev/nvme0n1p3 on /mnt/custom type btrfs (rw,relatime,ssd,space_cache)
> 
> I can create files in here but cannot do anything btrfs-y
> 
> % btrfs filesystem show /mnt/custom
> ERROR: not a valid btrfs filesystem: /mnt/custom
> 
> % btrfs subvolume create /mnt/custom/test
> Create subvolume '/mnt/custom/test'
> ERROR: cannot create subvolume: Inappropriate ioctl for device
> 
> Google has been no help at all.

Neil,

I've got a similar drive in my desktop and it actually works.
Difference: I am using Ext4.

Can you try Ext4 and see if it works? 
Next test: Does it work with a non-NVMe drive?

Also, which kernel version?

--
Joost