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

Rafael J. Wysocki
2015-11-30T01:41:29Z

On Monday, November 30, 2015 09:20:06 AM Jiang Liu wrote:
> 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@linux.intel.com>
> >>
> >> 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@internode.on.net>.
> >> 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@linux.intel.com>
> >> Reported-and-tested-by: Arthur Marsh <arthur.marsh@internode.on.net>
> >> Cc: Keith Busch <keith.busch@intel.com>
> >> Cc: Arthur Marsh <arthur.marsh@internode.on.net>
> >> Cc: Hans de Bruin <jmdebruin@xmsnet.nl>
> >
> > 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.

OK, thanks.

Keith, Hans, can you test this version too please?

Bjorn, any more comments from you on this one?

> >> ---
> >> 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,
> >>
> >

Thanks,
Rafael