Re: [PATCH v1] block/nvme: introduce PMR support from NVMe 1.4 spec

[Stefan Hajnoczi]

Hi Andrzej,
After having looked at the PMRWBM part of the spec, I think that the
Bit 1 mode should be implemented for slightly better performance.  Bit
0 mode is not well-suited to virtualization for the reasons I
mentioned in the previous email.

The spec describes Bit 1 mode as "The completion of a read to the
PMRSTS register shall ensure that all prior writes to the Persistent
Memory Region have completed and are persistent".

Stefan