Re: [PATCH] PCI/AER: Prevent runtime power management during recovery

[Keith Busch <keith.busch@intel.com>]

On Tue, Jun 12, 2018 at 01:21:53PM +0530, poza@codeaurora.org wrote:
> On 2018-06-12 10:10, Sinan Kaya wrote:
> > On 6/11/2018 6:29 PM, Keith Busch wrote:
> > > A bridge that supports D3 but not hotplug will be subject to runtime
> > > power management placing it in a non-operation power state if it
> > > doesn't
> > > have any devices attached. This patch will prevent this power
> > > management
> > > during error recovery so that the rescan at the end may be successful.
> > 
> > If there is no card connected, why would the bridge observe a fatal
> > error?
> 
> fatal error could be coming from anywhere let us say below RootPort..
> and RP observes it and decides to take the tree down....
> Is that the case Keith is talking about ?

Right, the err fatal handling removes all the devices below a bridge,
making that bridge allowed for run time d3.
 
> Why will re-enumeration be a problem even if runtime PM is active ?
> I assume that enumeration will get bridge out of D3.

That doesn't seem to be the case.