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

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

On Sun, Feb 14, 2010 at 02:51:17PM +0100, Rafael J. Wysocki wrote:
> On Saturday 13 February 2010, Gary Hade wrote:
> > On Sat, Feb 13, 2010 at 01:20:29AM +0100, Rafael J. Wysocki wrote:
> > > On Friday 12 February 2010, Rafael J. Wysocki wrote:
> > > > On Friday 12 February 2010, Gary Hade wrote:
> ...
> > > In fact there are two problems in there.  First, the bridge event notification
> > > calls handle_bridge_insertion() which attempts to install a PM notifier for
> > > the bridge and that deadlocks, because it tries to acquire the mutex
> > > recursively.  Second, apparently, init_bridge_misc() may be called in the
> > > notification code path and it attempts to unregister the notifier and register
> > > it again, which can't be done with pci_acpi_notify_mtx held.
> > > 
> > > I guess there are similar problems on the hot remove notification path.
> > > 
> > > Anyway, I have a new version of the patch and I'm going to test it a bit
> > > over the weekend.  Unfortunately, I don't have hardware with PCI hotplug
> > > capability, so I'll send you the new patch for testing on Monday, if you don't
> > > mind.
> > 
> > I don't mind.
> 
> Thanks!
> 
> > Although I am concerned that my acpiphp only
> > testing on our IBM System x boxes may not be sufficient to
> > assure that PCI hotplug will work well on other PCI hotplug
> > capable systems.  I hope that others will also do some early
> > testing of this code.
> 
> The code that you've been testing is not very hardware-dependent.  It only
> matters whether or not the hardware is capable of PCI hotplugging
> (ACPI-based), so your testing should be sufficient.

Perhaps the tester-dependent aspect should also be considered. :)

> 
> In fact I have two patches to test.  The first one is an ACPI CA patch that
> allows us to use more than one system notify handler per device (below).
> Please test it on top of [1-3/9] with the replacement for [4-6/9] I sent
> you earlier (http://patchwork.kernel.org/patch/78814/) and (updated) [7/9].

This seemed to work OK.  I did not see any of the previously
reported issues during hot-remove and hot-add.

> 
> If this works, please apply the patch from
> http://git.kernel.org/?p=linux/kernel/git/rafael/suspend-2.6.git;a=patch;h=d42c8b334bafe3a15f2dd43e395dafefe58dc588
> on top of the appended one and see if things still work correctly.

Results still looked good after adding this patch.

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