Re: [PATCH 1/1] usb: hub: Fix flushing and scheduling of delayed work that tunes runtime pm

[Mathias Nyman <mathias.nyman@linux.intel.com>]

On 27.6.2025 12.58, Mark Brown wrote:
> On Thu, Jun 26, 2025 at 04:01:02PM +0300, Mathias Nyman wrote:
>> Delayed work to prevent USB3 hubs from runtime-suspending immediately
>> after resume was added in commit 8f5b7e2bec1c ("usb: hub: fix detection
>> of high tier USB3 devices behind suspended hubs").
>>
>> This delayed work needs be flushed if system suspends, or hub needs to
>> be quiesced for other reasons right after resume. Not flushing it
>> triggered issues on QC SC8280XP CRD board during suspend/resume testing.
>>
>> Fix it by flushing the delayed resume work in hub_quiesce()
> 
> I'm seeing NFS boot failures on the Raspberry Pi 3B+ in pending-fixes
> which bisect to this commit.  The networking fails to come up so the
> rootfs can't be mounted, the ethernet on these boards is USB based.
> 
> Full log:
> 
>     https://lava.sirena.org.uk/scheduler/job/1516948#L1142
> 

Thanks for the report

The Raspberry Pi 3B+ doesn't have USB3 ports, so it should not be due
to pending post resume work.

The same hub->init_work is however used for other purposes as well, it
could be that we end up flushing some other work.

If I write a v2 patch that puts this post resume work into its own
dedicated work item, and only flushes that, could you try it out
on the Raspberry Pi 3B+

Same with the QC SC8280XP CRD board, would be grateful if Konrad could
try out a version 2.

Thanks
Mathias