Reset and power cycle with qpair remaining about pynvme

[cranechu]

Hi, Catogts,

Yes, that is an issue working in progress. In dirty power off, we have to shut the power off before closing iowoker, in order to create a real dirty power off test scenario. However, when ioworker try to close its qpair, the drive is offline, so cannot response any command, like delete SQ/CQ, and then many abnormal behaviors could happen, as you mentioned above.

It is just an experimental feature, and not fully tested in the up coming release. We are working on it to make the dirty power off more smooth and reliable.

It happens only in dirty power cycle test, while the clean power cycle test is robust which closes qpair before power off.

Thanks,
-Crane