Re: [linux-pm] [PATCH 8/9] PCI / ACPI / PM: Platform support for PCI PME wake-up (rev. 7)

[Gary Hade <garyhade@us.ibm.com>]

On Tue, Feb 09, 2010 at 09:19:51PM +0100, Rafael J. Wysocki wrote:
> On Tuesday 09 February 2010, Gary Hade wrote:
> > On Tue, Feb 09, 2010 at 08:41:16AM -0800, Gary Hade wrote:
> > > On Tue, Feb 09, 2010 at 01:48:20PM +0100, Rafael J. Wysocki wrote:
> > > > On Tuesday 09 February 2010, Gary Hade wrote:
> > > > > On Mon, Feb 08, 2010 at 03:37:08PM -0800, Gary Hade wrote:
> > > > > > On Mon, Feb 08, 2010 at 10:30:30PM +0100, Rafael J. Wysocki wrote:
> > > > > > > On Monday 08 February 2010, Rafael J. Wysocki wrote:
> > > > > > > > On Monday 08 February 2010, Gary Hade wrote:
> > > > > > > > > On Sat, Feb 06, 2010 at 09:11:56PM +0100, Rafael J. Wysocki wrote:
> > > > > > > > > > On Saturday 06 February 2010, Bjorn Helgaas wrote:
> > > > > > > > > > > On Sunday 10 January 2010 07:01:03 am Rafael J. Wysocki wrote:
> > > > > > > > > > > > From: Rafael J. Wysocki <rjw@sisk.pl>
> > > > > > > > > > > > 
> > > > > > > > > > > > Although the majority of PCI devices can generate PMEs that in
> > > > > > > > > > > > principle may be used to wake up devices suspended at run time,
> > > > > > > > > > > > platform support is generally necessary to convert PMEs into wake-up
> > > > > > > > > > > > events that can be delivered to the kernel.  If ACPI is used for this
> > > > > > > > > > > > purpose, a PME generated by a PCI device will trigger the ACPI GPE
> > > > > > > > > > > > associated with the device to generate an ACPI wake-up event that we
> > > > > > > > > > > > can set up a handler for, provided that everything is configured
> > > > > > > > > > > > correctly.
> > > > > > > > > > > 
> > > > > > > > > > > I think acpiphp needs a little attention after this patch.  Gary
> > > > > > > > > > > Hade noticed while testing Jesse's linux-next branch that acpiphp
> > > > > > > > > > > complains like this:
> > > > > > > > > > > 
> > > > > > > > > > >   acpiphp: ACPI Hot Plug PCI Controller Driver version: 0.5
> > > > > > > > > > >   acpiphp: Slot [9] registered
> > > > > > > > > > >   acpiphp: Slot [10] registered
> > > > > > > > > > >   acpiphp_glue: failed to register interrupt notify handler
> > > > > > > > > > >   acpiphp: Slot [6] registered
> > > > > > > > > > >   acpiphp_glue: failed to register interrupt notify handler
> > > > > > > > > > > 
> > > > > > > > > > > I reproduced this on an HP rx3600 (ia64), and found that acpiphp
> > > > > > > > > > > doesn't complain on commit 82533a617f453, but it *does* complain
> > > > > > > > > > > on commit fb3383bb4ac6e, which seems to be this patch.
> > > > > > > > > > 
> > > > > > > > > > I can't see the possible reason looking at the code alone.
> > > > > > > > > > 
> > > > > > > > > > Could you add a debug printk() printing the error code returned by
> > > > > > > > > > pci_acpi_add_hp_notifier() in acpiphp_glue.c:register_slot(), please?
> > > > > > > > > 
> > > > > > > > > Rafael, On the system where I ran into the problem it returns
> > > > > > > > > AE_NOT_FOUND.  See below.
> > > > > > > > 
> > > > > > > > Thanks!
> > > > > > > > 
> > > > > > > > Well, that means there's no struct acpi_device object associated with handle.
> > > > > > > > 
> > > > > > > > I must admit I didn't take that into consideration, but it should be easily
> > > > > > > > fixable.  I'll send a patch for that later today.
> > > > > > > 
> > > > > > > Patch appended.
> > > > > > > 
> > > > > > > If the theory is correct, it should fix the issue.  Please test.
> > > > > > 
> > > > > > Well, acpiphp now loads OK with no disturbing messages:
> > > > > > [  247.360878] pci_hotplug: PCI Hot Plug PCI Core version: 0.5
> > > > > > [  247.385048] acpiphp: ACPI Hot Plug PCI Controller Driver version: 0.5
> > > > > > [  247.385459] acpiphp_glue: found PCI host-bus bridge with hot-pluggable slots
> > > > > > [  247.385486] acpiphp_glue: found ACPI PCI Hotplug slot 1 at PCI 0000:02:01
> > > > > > [  247.385519] acpiphp: Slot [1] registered
> > > > > > [  247.386167] acpiphp_glue: found PCI host-bus bridge with hot-pluggable slots
> > > > > > [  247.386196] acpiphp_glue: found ACPI PCI Hotplug slot 2 at PCI 0000:06:01
> > > > > > [  247.386225] acpiphp: Slot [2] registered
> > > > > > [  247.386828] acpiphp_glue: found PCI-to-PCI bridge at PCI 0000:0a:00.0
> > > > > > [  247.386861] acpiphp_glue: found ACPI PCI Hotplug slot 3 at PCI 0000:0b:00
> > > > > > [  247.386902] acpiphp: Slot [3] registered
> > > > > > [  247.387564] acpiphp_glue: found PCI-to-PCI bridge at PCI 0000:0f:00.0
> > > > > > [  247.387597] acpiphp_glue: found ACPI PCI Hotplug slot 4 at PCI 0000:10:00
> > > > > > [  247.387620] acpiphp: Slot [4] registered
> > > > > > [  247.388293] acpiphp_glue: found PCI-to-PCI bridge at PCI 0000:14:00.0
> > > > > > [  247.388324] acpiphp_glue: found ACPI PCI Hotplug slot 5 at PCI 0000:15:00
> > > > > > [  247.388347] acpiphp: Slot [5] registered
> > > > > > [  247.389041] acpiphp_glue: found PCI-to-PCI bridge at PCI 0000:19:00.0
> > > > > > [  247.389077] acpiphp_glue: found ACPI PCI Hotplug slot 6 at PCI 0000:1a:00
> > > > > > [  247.389114] acpiphp: Slot [6] registered
> > > > > > [  247.389736] acpiphp_glue: Bus 0000:1a has 1 slot
> > > > > > [  247.389739] acpiphp_glue: Bus 0000:15 has 1 slot
> > > > > > [  247.389742] acpiphp_glue: Bus 0000:10 has 1 slot
> > > > > > [  247.389746] acpiphp_glue: Bus 0000:0b has 1 slot
> > > > > > [  247.389748] acpiphp_glue: Bus 0000:06 has 1 slot
> > > > > > [  247.389751] acpiphp_glue: Bus 0000:02 has 1 slot
> > > > > > [  247.389753] acpiphp_glue: Total 6 slots
> > > > > > 
> > > > > > However, I didn't have a chance to confirm that hot-add of a
> > > > > > PCI card works correctly before someone else swiped the system
> > > > > > from me for a while.  I will verify this when I get it back,
> > > > > > hopefully later today.
> > > > > 
> > > > > I got the system back but unfortunately have some bad news.
> > > > > The system has 2 hotpluggable PCI-X slots and 4 hotpluggable
> > > > > PCIe slots.  I tried hot-adding both a PCI-X card and a PCIe
> > > > > card but acpiphp did not seem to see the hot-add event for
> > > > > either card.  acpiphp was loaded with debug=1 and issued no
> > > > > messages when I added the cards.
> > > > 
> > > > I gather it works without the $subject patch?
> > > 
> > > I don't know for sure.  Late Friday after running into the handler
> > > registration issue I reverted 8/9 which required hand fixup for
> > > one hunk failure.  I then got some compile errors which I assumed
> > > may be related to my non-removal of some of the other patches in the
> > > series.  I started reverting the entire series but got a failure right
> > > away with 9/9 but didn't take the time to try to resolve it.
> > > 
> > > Since it sounds like you are doubtful that your changes are
> > > responsible for this new issue I will try to make time to fuss
> > > with this more today.
> > 
> > Rafael, I think I can approach this from a different direction.
> > Except for a trivial failure with 9/9, the entire series applies
> > to 2.6.33-rc7.  I will try hot-add with 2.6.33-rc7 with and without
> > your patches and let you know what happens.
> 
> Yes, please, but  you may want to test the appended patch first.
> 
> If I think correctly what the problem is, it should work.

OK.  I already confirmed that the problem reproduces with your
patches applied.  I am now in the process of trying vanilla
2.6.33-rc7.  If hot-add works with 2.6.33-rc7 I will give
your patch a try.

Thanks!

Gary

-- 
Gary Hade
System x Enablement
IBM Linux Technology Center
503-578-4503  IBM T/L: 775-4503
garyhade@us.ibm.com
http://www.ibm.com/linux/ltc