[PATCH V2 1/2] nvme: Include AEN CQE.DW1 in NVME_AEN uevents

[Christoph Hellwig]

On Thu, Sep 29, 2022 at 03:39:54PM -0700, clay.mayers at kioxia.com wrote:
> From: Clay Mayers <clay.mayers at kioxia.com>
> 
> There are AENs from alternate command sets that include
> extra data in their AEN's CQE.DW1.  For example, the ZNS
> Zone-Descriptor-Changed AEN uses it to indicate the NSID
> of the event's log page.
> 
> NVME_AEN uevent now includes the value of CQE.DW1 as a new
> property.  It is only included when non-zero to keep previously
> existing uevents unmodified.

I don't think we can actually do this.  If we ever want to handle
Zone Excursions or any other event where the device can chane the
Zone Descriptor we need to handle this AEN in the kernel and thus
control the clearing of the even by reading the associated log page,
so we can't just send it on to userspace.  This is a bit of a sad
state of affairs but unavoidable due to the NVMe AEN design.