[PATCH] driver core: fix async device shutdown hang

[Laurence Oberman]

On Wed, 2024-09-18 at 08:12 +0200, Greg Kroah-Hartman wrote:
> On Tue, Sep 17, 2024 at 07:20:41PM -0500, stuart hayes wrote:
> > 
> > 
> > On 9/17/2024 3:42 PM, Greg Kroah-Hartman wrote:
> > > On Tue, Sep 17, 2024 at 03:15:17PM -0500, Stuart Hayes wrote:
> > > > Modify device_shutdown() so that supplier devices do not wait
> > > > for
> > > > consumer devices to be shut down first when the devlink is sync
> > > > state
> > > > only, since the consumer is not dependent on the supplier in
> > > > this case.
> > > > 
> > > > Without this change, a circular dependency could hang the
> > > > system.
> > > > 
> > > > Signed-off-by: Stuart Hayes <stuart.w.hayes at gmail.com>
> > > 
> > > What commit id does this fix?  Should it go to stable?
> > > 
> > > And what driver is causing this problem, is this a regression or
> > > for
> > > something new that just got added to the tree?
> > > 
> > > thanks,
> > > 
> > > greg k-h
> > 
> > This fixes commit 8064952c65045f05ee2671fe437770e50c151776, in
> > driver-core-next & linux-next... it's problem with code that was
> > just
> > added to the tree (in drivers/base/core.c).  It is not in stable.
> 
> Ah, that wasn't obvious, sorry.
> 
> > Apologies, I should have mentioned that from the start.
> 
> Can you resend this with a "Fixes:" tag in it so I can just take it
> that
> way and not have to edit it by hand?
> 
> thanks,
> 
> greg k-h
> 

FYI 
This patch plus the rest of the original Bundle has been tested 
at Red Hat on a system with 24 nvme devices. 
Improvement was almost 8 times faster to shutdown.

Tested-by: Laurence Oberman <loberman at redhat.com>