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

[Jiang Liu]

On 2015/11/28 0:06, Rafael J. Wysocki wrote:
> On Friday, November 27, 2015 11:12:33 AM 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>
>> Cc: Keith Busch <keith.busch@xxxxxxxxx>
>> Cc: Arthur Marsh <arthur.marsh@xxxxxxxxxxxxxxxx>
>> Cc: Hans de Bruin <jmdebruin@xxxxxxxxx>
> 
> What exactly has changed between this version and the previous one?
Hi Rafael,
	I have removed following changes against the original patch
posted at Nov 16.
 	       bus);

 	/* already added by acpi ? */
-	resource_list_for_each_entry(window, resources)
+	resource_list_for_each_entry(window, &info->resources)
 		if (window->res->flags & IORESOURCE_BUS) {
 			found = true;
 			break;
 		}
-
 	if (!found)
 		pci_add_resource(resources, &info->busn);

And I only refined the commit message based on the test patch
I sent to Authur as an attachment at Nov 25.
Thanks,
Gerry
> 
> 
>> ---
>>  arch/x86/pci/bus_numa.c |   13 ++-----------
>>  drivers/acpi/pci_root.c |    7 +++++++
>>  2 files changed, 9 insertions(+), 11 deletions(-)
>>
>> diff --git a/arch/x86/pci/bus_numa.c b/arch/x86/pci/bus_numa.c
>> index 7bcf06a7cd12..6eb3c8af96e2 100644
>> --- a/arch/x86/pci/bus_numa.c
>> +++ b/arch/x86/pci/bus_numa.c
>> @@ -50,18 +50,9 @@ void x86_pci_root_bus_resources(int bus, struct list_head *resources)
>>  	if (!found)
>>  		pci_add_resource(resources, &info->busn);
>>  
>> -	list_for_each_entry(root_res, &info->resources, list) {
>> -		struct resource *res;
>> -		struct resource *root;
>> +	list_for_each_entry(root_res, &info->resources, list)
>> +		pci_add_resource(resources, &root_res->res);
>>  
>> -		res = &root_res->res;
>> -		pci_add_resource(resources, res);
>> -		if (res->flags & IORESOURCE_IO)
>> -			root = &ioport_resource;
>> -		else
>> -			root = &iomem_resource;
>> -		insert_resource(root, res);
>> -	}
>>  	return;
>>  
>>  default_resources:
>> diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
>> index 850d7bf0c873..ae3fe4e64203 100644
>> --- a/drivers/acpi/pci_root.c
>> +++ b/drivers/acpi/pci_root.c
>> @@ -768,6 +768,13 @@ static void pci_acpi_root_add_resources(struct acpi_pci_root_info *info)
>>  		else
>>  			continue;
>>  
>> +		/*
>> +		 * Some legacy x86 host bridge drivers use iomem_resource and
>> +		 * ioport_resource as default resource pool, skip it.
>> +		 */
>> +		if (res == root)
>> +			continue;
>> +
>>  		conflict = insert_resource_conflict(root, res);
>>  		if (conflict) {
>>  			dev_info(&info->bridge->dev,
>>
> 
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