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

Gary Hade
2010-02-10T23:04:38Z

On Wed, Feb 10, 2010 at 11:58:00PM +0100, Rafael J. Wysocki wrote:
> On Wednesday 10 February 2010, Gary Hade wrote:
> > On Wed, Feb 10, 2010 at 10:42:11PM +0100, Rafael J. Wysocki wrote:
> > > On Wednesday 10 February 2010, Gary Hade wrote:
> > > > On Wed, Feb 10, 2010 at 07:00:54PM +0100, Rafael J. Wysocki wrote:
> > > > > On Wednesday 10 February 2010, Gary Hade wrote:
> > > > > > On Wed, Feb 10, 2010 at 02:12:29AM +0100, Rafael J. Wysocki wrote:
> > > > > > > On Wednesday 10 February 2010, Rafael J. Wysocki wrote:
> > > > > > > > On Wednesday 10 February 2010, Gary Hade wrote:
> > > > > > > > > On Tue, Feb 09, 2010 at 12:58:39PM -0800, Gary Hade wrote:
> > > > > > > > ...
> > > > > > > > > > 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.
> > > > > > > > >
> > > > > > > > > The hot-add worked fine with an unpatched 2.6.33-rc7.
> > > > > > > >
> > > > > > > > Good.
> > > > > > > >
> > > > > > > > > The new patch when added to the 2.6.33-rc7 tree that
> > > > > > > > > included the original patchset unfortunately did not
> > > > > > > > > correct the problem.
> > > > > > > >
> > > > > > > > Bad.
> > > > > > > >
> > > > > > > > Well, fortunately I have another one, but I haven't tested it myself yet except
> > > > > > > > for checking that it builds. Hopefully it won't break things more.
> > > > > > > >
> > > > > > > > The patch below applies on top of 2.6.33-rc7 with my PCI runtime PM patchset
> > > > > > > > applied. Please test it and let me know the results.
> > > > > > >
> > > > > > > Sorry, I sent a wrong version of the patch by mistake, it doesn't even build.
> > > > > > > The correct one is appended.
> > > > > >
> > > > > > No problem. I received this message before doing anything with
> > > > > > the previous one.
> > > > > >
> > > > > > Sorry, both hot-add and hot-remove behaviors appear unchanged
> > > > > > with this patch.
> > > > >
> > > > > Hmm, that's kind of strange. I'm getting suspicious.
> > > > >
> > > > > > I would like to dig into the code and help with the debugging
> > > > > > but I am swamped with other things right now. However, feel
> > > > > > free to continue using me for testing if you have other ideas
> > > > > > you want me to try.
> > > > >
> > > > > Thanks, of course I have some ideas. :-)
> > > > >
> > > > > First, please try to test 2.6.33-rc7 with patches [1/9] - [7/9] applied
> > > > > (ie. without the $subject patch and [9/9]). Let's make sure we're debugging
> > > > > the right patch.
> > > >
> > > > It does look like both the hot-add and hot-remove issues were
> > > > introduced by something in 1/9 through 7/9. I started with a
> > > > clean 2.6.33-rc7 tree and applied only 1/9 through 7/9. I still
> > > > see that lingering blinking amber LED with hot-remove and no
> > > > response from the driver during hot-add.
> > > >
> > > > Now I suppose you want me to start reverting 1/9 through 7/9
> > > > in reverse order to find the culprit. :)
> > >
> > > Actually, I think [6/9] is the offending one, so please try with [1/9] - [5/9]
> > > applied and if that works, please apply [6/9] and retest to confirm it's the
> > > culprit.
> >
> > Yes, 6/9 also appeared to be the most likely suspect to me and
> > I was already doing what you asked except in the opposite order.
> > With 1/9 through 6/9 both the hot-add and hot-remove issues still
> > reproduced. After removing 6/9 both issues disappeared.
>
> Thanks for verifying, I've already started to look for bugs in it.

Thanks!

>
> What's your kernel command line, BTW?

root=/dev/disk/by-id/scsi-35000c5000036ffcb-part7 ip=9.47.66.9:9.47.67.50:9.47.66.1:255.255.254.0 resume=/dev/disk/by-id/scsi-35000c50000370247-part3 crashkernel=256M-:128M console=tty0 console=ttyS0,115200 pci=use_crs pci=norom

Gary

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