NVMe suspend failure

[Bart Van Assche]

On 2/5/24 09:58, Keith Busch wrote:
> On Sat, Feb 03, 2024 at 05:44:03PM -0800, Bart Van Assche wrote:
>> On 2/3/24 17:18, Keith Busch wrote:
>>> And this is happening during a suspend? What kind of suspend? Like an
>>> S3/S4, or idle suspend?
>>
>> I'm not sure how to determine this? This is what I found in the logs:
>>
>> Feb 03 09:02:20 asus systemd-logind[1208]: The system will suspend now!
>> Feb 03 09:02:20 asus systemd-logind[1208]: Unit suspend.target is masked,
>> refusing operation.
> 
> I am not sure what the "suspend now!" message means to the driver. Your
> initial report with the "CSTS=0xfffffff" comes from the nvme request
> timeout handler, so I'd want to confirm what command is timing out, and
> what path dispatched it: was the command dispatched from nvme_suspend()
> path, or is this coming from somewhere else? If somewhere else, was it
> dispatched before or after the nvme_suspend?

Hi Keith,

I think the requests that timed out were submitted after resume. User space
software is paused before nvme_suspend() is called. nvme_suspend() waits for
pending requests to complete. Hence, the requests that timed out must have
been submitted after user space processes were resumed. An additional
indication is that I saw user space software crash after resume that writes
periodically to block storage devices (email client and web browser).

Thanks,

Bart.