Should NVME_SC_INVALID_NS be translated to BLK_STS_IOERR instead of BLK_STS_NOTSUPP so that multipath(both native and dm) can failover on the failure?

[Jirong Feng]

> So essentially there is no need for the host side patch? interesting. 
> Are you sure?

At least no failure is observed in a newer version(6.6.0) of kernel so 
far. I can only tell that I've tested it for hundreds of times.

In addition, I've got some scripts to enable/disable it continually, we 
can observe it a few more days.


> Can you please also try with mpath iopolicy=round-robin?
All my previous tests were done with round-robin. I retested again today 
both round-robin and numa, the results are still the same.


> I'm asking because I cannot understand what is preventing this path 
> from being selected again and
> again for I/O....

Perhaps we need to dive into the code of old 
version(4.18.0-147.3.1.el8_1) and see what's different?

Or should I try apply the host side patch to the old version and test again?


Thanks