Re: [RFC PATCH] nvme: refuse an unsolicited format change on a namespace that is in use

[Chris S]

On Tue, Aug 11, 2026 at 4:42 PM Keith Busch <kbusch@xxxxxxxxxx> wrote:
>
> You need a nvme spec level change for this to work. There's nothing we
> can do today to close every race where the driver attempts to use a
> stale LBA shift when the format was changed externally.

Got you. I understand now. Thanks for pointing that out.

>
> What I proposed in the past was that the device has to return a new
> error code for all new IO until the host queries the appropriate
> Namespace identification to acknowledge the new LBA format. Kind of like
> a SCSI "Check Condition Parameters Changed". An enlightend host could
> trigger a queue freeze and namespace rescan after seeing this status,
> clearing the device's latch and resume IO after setting up the new queue
> limits.

I think you are right for this. And I think this is a right solution.
Thanks for sharing your thoughts! Helped much.

Best,
Chao