[Qemu-devel] Question about vNVDIMM file format

[Richard W.M. Jones]

I'm playing with ext4 and DAX.

I'm using:

  -object memory-backend-file,id=mem1,share,mem-path=/var/tmp/pmem,size=4G \
  -device nvdimm,memdev=mem1,id=nv1

where /var/tmp/pmem is a 4 GB ext4 filesystem image (no partition
table).  I can mount this in the guest using:

  mount -o dax /dev/pmem0 /mnt

and everything appears to work.

I read in the mailing list that the pmem file has some internal
structure for storing config data, stored in the last 128 KB of the
file.  Is that still the case?

Rich.

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