Re: ACPI hotplug panic with current git head

[Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>]

James Bottomley wrote:
> On Mon, 2009-01-19 at 12:11 +0900, Kenji Kaneshige wrote:
>> I'm sending the debug patch against 2.6.29-rc1 below. I'm also
>> sending it as an attachment. It also contains the code to prevent
>> the kernel panic from you. Please note that you will see two
>> WARN_ON(1) messages with the patch. Those are shown by my debug
>> patch.
>>
>> Could you try it and send me the whole dmsg output?
> 
> Actually, the machine is now running -rc2, so the patch doesn't quite
> apply: 
> 
> jejb@sparkweed> patch -p1 < ~/tmp.diff
> patching file include/linux/pci-acpi.h
> patching file drivers/pci/hotplug/acpiphp_glue.c
> Hunk #1 FAILED at 266.
> Hunk #2 succeeded at 467 (offset 2 lines).
> Hunk #3 succeeded at 489 (offset 2 lines).
> Hunk #4 succeeded at 518 (offset 2 lines).
> Hunk #5 succeeded at 556 (offset 2 lines).
> 
> Looks like the rejection is in the NULL check piece, so I've already
> actually sent you the information it would produce.
> 
> The dmesg output is pretty big, below.
> 

Thank you very much, James.

Thanks to you, I found the root cause of the
problem. The acpi_pci_get_bridge_handle() function assumes
pci_bus->self is NULL on the root bus. But it is not true
and pci_bus->self can have a non-NULL value on some
platfroms (like yours). So it must check pci_bus->parent
instead.

I found some other code that has the same wrong assumption.
I'll make a fix for them and send it soon.

Thanks,
Kenji Kaneshige