Re: [GIT PULL] PCI fixes for v4.10

[Bjorn Helgaas]

On Thu, Feb 09, 2017 at 09:09:50AM -0600, Bjorn Helgaas wrote:
> [+cc Ashok, Keith]
> 
> On Thu, Feb 09, 2017 at 05:06:48AM +0100, Lukas Wunner wrote:
> > On Wed, Feb 08, 2017 at 01:22:56PM -0600, Bjorn Helgaas wrote:
> > > Bjorn Helgaas (1):
> > >       Revert "PCI: pciehp: Add runtime PM support for PCIe hotplug ports"
> > 
> > What's the rationale for reverting this?
> > 
> > You've received patches to fix the issue on both affected machines,
> > so a revert seems unnecessary:
> > 
> > https://patchwork.kernel.org/patch/9557113/
> > https://patchwork.kernel.org/patch/9562007/
> 
> I don't think we've gotten to the root cause of the problem yet,
> and I don't want to throw in fixes at the last minute without a better
> understanding of it.
> 
> PCIe hotplug hardware is not very complicated, it hasn't changed in
> many years, and at least for the Intel hardware in question, is
> generally pretty well-tested with Windows.  So I want to be careful
> about asserting that this new piece of hardware is broken.

I apologize: I had quirks on the brain, but neither of the patches
above is device-specific.  So neither is claiming broken hardware.

However, 9557113 claims we get unwanted PME interrupts if the slot is
occupied when we suspend to D3hot.  This is what I want to explore
further, because that hardware behavior doesn't really make sense to
me.

9562007 apparently fixes something, but at this point it's a debugging
patch (no changelog or signed-off-by) so not a candidate for tossing
into v4.10 at this late date.

Bjorn