Not tried on Xavier, but similar issue was seen on TX1 and TX2.
I have built a kernel on TX2 enabling SMB2 and SMB311 support, and the following command no longer complains about invalid argument:
sudo mount -t cifs -o username=myusername,domain=domainname,sec=ntlmv2,vers=3.11 //<server_ip>/<share_name> /mnt/tmp/
I have no SMB3.11 share for full testing, but I think this is the solution.