How to turn on SMB3 POSIX extensions in Samba server?

[Jeremy Allison]

On Sat, Oct 05, 2019 at 10:49:59PM +0100, Rowland penny via samba-technical wrote:
> > 
> > Jeremy.
> > 
> Hi Jeremy, I advised the OP over on the samba mailing that unix extensions
> for SMBv3 do not exist yet, but he seems to think that something similar
> should work with mount.cifs and the kernel.

Yeah, that's Steve pushing experimental stuff into
released kernels for you :-(. The client side of the
SMBv3 UNIX extensions is being developed in the
SMB3 Linux kernel client code, the server side isn't
in any released Samba (or even upstream master) yet.