Re: [PATCH v3 18/21] nvme: Update CCR completion wait timeout to consider CQT

[Hannes Reinecke <hare@suse.de>]

On 2/20/26 03:01, Randy Jennings wrote:
> Hannes,
> 
>> (ctrl->kato * 1000) + ctrl->cqt
> As Mohamed pointed out, we have already received a response from a CCR
> command.  The CCR, once accepted, communicates the death of the
> connection to the impacted controller and starts the cleanup tracked
> by CQT.  So, no need to wait for the impacted controller to figure out
> the connection is down.
> 
> The max(cqt, kato) was just to give some wait time that should allow
> issuing a CCR again from a different controller (in case of losing
> communication with this one).  It certainly does not need to be longer
> than cqt (and it should be no longer than the remaining duration of
> time-based retry; that should get addressed at some point).  I cannot
> remember why kato (if larger; I expect it would be smaller) made sense
> at the time.
> 
Because we have to wait for the AEN, at which point KATO comes into
play yet again.
So max(CQT, KATO) is the appropriate waiting time for that.

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                  Kernel Storage Architect
hare@suse.de                                +49 911 74053 688
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