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

From: Rafael J. Wysocki
Date: Mon Feb 15 2010 - 16:42:23 EST


On Monday 15 February 2010, Gary Hade wrote:
> 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.

Thanks a lot for testing, it looks like the issues have been resolved, then.

Rafael
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