Re: [Bugfix] x86/PCI: Fix regression caused by commit 4d6b4e69a245

[Jiang Liu]

On 2015/11/25 6:19, Rafael J. Wysocki wrote:
> On Tue, Nov 24, 2015 at 5:49 PM, Bjorn Helgaas <helgaas@xxxxxxxxxx> wrote:
>> On Mon, Nov 16, 2015 at 12:27:37PM +0800, Jiang Liu wrote:
>>> From: Liu Jiang <jiang.liu@xxxxxxxxxxxxxxx>
>>>
>>> Commit 4d6b4e69a245 ("x86/PCI/ACPI: Use common interface to support
>>> PCI host bridge") converted x86 to use the common interface
>>> acpi_pci_root_create, but the conversion missed on code piece in
>>> arch/x86/pci/bus_numa.c, which causes regression on some legacy
>>> AMD platforms as reported by Arthur Marsh <arthur.marsh@xxxxxxxxxxxxxxxx>.
>>> The root causes is that acpi_pci_root_create() fails to insert
>>> host bridge resources into iomem_resource/ioport_resource because
>>> x86_pci_root_bus_resources() has already inserted those resources.
>>> So change x86_pci_root_bus_resources() to not insert resources into
>>> iomem_resource/ioport_resource.
>>
>> Fixes: 4d6b4e69a245 ("x86/PCI/ACPI: Use common interface to support PCI host bridge")
>>
>>> Signed-off-by: Jiang Liu <jiang.liu@xxxxxxxxxxxxxxx>
>>> Reported-and-tested-by: Arthur Marsh <arthur.marsh@xxxxxxxxxxxxxxxx>
>>
>> What's the status of this?  It looks like a regression we need to fix
>> for v4.4.
>>
>> AFAICT, Arthur did *not* test this patch (rather, his response says he
>> did test it and the test failed).
>>
>> 4d6b4e69a245 was merged by Rafael, and I assume he'll merge the fix
>> unless I hear otherwise.
> 
> Quite frankly, I'm more likely to revert the offending commit at this
> point as that's not the only regression reported against it and the
> fix only helps in one case (out of three known to me).
Hi Rafael,
	I got regression report from Hans de Bruin<jmdebruin@xxxxxxxxx>,
Keith Busch <keith.busch@xxxxxxxxx>, and Arthur Marsh
<arthur.marsh@xxxxxxxxxxxxxxxx>. Hans and Keith also reports
the patch fixes the regression. For Arthur's case, the debug
patch works for him, but the formal patch based on the debug
patch fails, so I need to do more investigation about this.
Is there any other report related to commit 4d6b4e69a245 so
I could help to investigate?
Thanks,
Gerry

> 
> Thanks,
> Rafael
> 
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