[PATCH 1/5] driver core: Support two-pass driver shutdown.

[Bjorn Helgaas]

On Wed, Feb 14, 2024 at 01:36:28PM -0800, Saravana Kannan wrote:
> On Wed, Feb 14, 2024 at 12:10 AM Christoph Hellwig <hch at lst.de> wrote:
> > On Tue, Feb 13, 2024 at 07:36:35PM -0800, Saravana Kannan wrote:
> > > > This changes the bus driver interface with an additional entry point
> > > > to enable devices to implement two-pass shutdown. The existing
> > > > synchronous interface to shutdown is called, and if a shutdown_wait
> > > > method is defined the device is moved to an alternate list.
> > >
> > > This sounds more like you need a parallelized async shutdown than a
> > > two-pass shutdown. Similar to how async probes are done today. Why not
> > > do that so it'll actually be useful in a more general fashion? You can
> > > even add a flag like we have for probes so that drivers don't need to
> > > do anything special to allow this parallelism.
> >
> > Well, we had that discussion before.
> 
> Can you point me to this please? I looked around and wasn't able to
> find it.

I'm not sure what Christoph had in mind, but he might be referring to
this:
https://lore.kernel.org/r/20231227203337.GA1509884@bhelgaas

Bjorn