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 ** Changed in: ndctl (Ubuntu Focal) Status: Confirmed => Invalid ** Changed in: qemu (Ubuntu Focal) Status: Confirmed => Invalid -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1855177 Title: QEMU emulated nvdimm regions alignment need (128MB) or ndctl create- namespace namespace1.0 might fail To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1855177/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs