Re: [PATCH 1/1] nvme: retry security commands if media not ready

[Christoph Hellwig <hch@lst.de>]

On Thu, Oct 03, 2024 at 06:35:30PM -0500, Greg Joyce wrote:
> I agree, I wonder about the value/wisdom of the CC.CRIME capability
> especially since there is no way to read status that indicates that the
> media is ready for the Figure 103 commands. But it is a defined feature
> and setting it does cause CSTS.RDY to be asserted before the media is
> ready.
> 
> The Kioxia CM7 drive does set both CRWMS and CRIMS (CRMS=11b). And
> these lines in the NVMe driver thus set CC.CRIME:
> 
>         if (ctrl->cap & NVME_CAP_CRMS_CRWMS && ctrl->cap &            
> NVME_CAP_CRMS_CRIMS)
>                 ctrl->ctrl_config |= NVME_CC_CRIME;
> 
> After reading more of the spec and driver code and discussions here, I
> suggest that those two lines be removed. This has the effect of
> returning to the NVMe version 1.4 behavior and CSTS.RDY will not be
> asserted until the media is ready for commands.

Well, it is a useful feature unless random admin commands return
not ready.  Which got weaseld into the spec, but really should not
happen to make the feature useful.  So I think we'll need to put the
workaround in instead of messing up the proper implementations of
the feature that aren't this silly.  And make sure the big companies
put that into their purchase specs.