Comment 8 for bug 1855177

You have to make sure to set the label size as the same size as the minimum alignment required. For QEMU emulation I found it to be 2M, and, in this case, you can correctly work with 2 or more nvdimms. With proper alignment, you can also re-create namespaces - of other mode like devdax or fsdax - if you already have a namespace working.

Example:

    <!-- nvdimm node 0 -->
    <memory model='nvdimm' access='shared'>
      <source>
        <path>$_nvpath1</path>
      </source>
      <target>
        <size unit='KiB'>1048576</size>
        <node>0</node>
        <label>
          <size unit='KiB'>2048</size>
        </label>
      </target>
      <address type='dimm' slot='0'/>
    </memory>
    <!-- nvdimm node 1 -->
    <memory model='nvdimm' access='shared'>
      <source>
        <path>$_nvpath2</path>
      </source>
      <target>
        <size unit='KiB'>1048576</size>
        <node>1</node>
        <label>
          <size unit='KiB'>2048</size>
        </label>
      </target>
      <address type='dimm' slot='1'/>
    </memory>

So I'm closing this as NOT A BUG as the alignment can be configured accordingly.

For other examples you can check autopkgtests being proposed as a merge request at:

https://bugs.launchpad.net/ubuntu/+source/ndctl/+bug/1853506