Re: warn_slowpath_common in drivers/pci/search.c:44 on linux-3.4.0

[Joerg Roedel <joerg.roedel@amd.com>]

On Tue, May 29, 2012 at 10:56:50AM +0200, Antonio Quartulli wrote:
> attached!
> Some days ago I tried to put some printk in the code and, as far as I can
> understand, you are right.

Hmm, looks like device 03:00.0 is a 32bit PCI device attached to device
00:1c.2 which calls itself a Root Port instead of a PCI Bridge. I am
not sure if the check in search.c is really necessary. As I see it there
are also other possible pcie_types like PCI_EXP_TYPE_PCIE_BRIDGE.
Putting Anil Keshavamurthy on Cc.

Anil, is this check in pci_find_upstream_pcie_bridge() really
necessary:

        /* PCI device should connect to a PCIe bridge */
        if (pdev->pcie_type != PCI_EXP_TYPE_PCI_BRIDGE) {
                /* Busted hardware? */
                WARN_ON_ONCE(1);
                return NULL;
        }

? In the warning that triggers for Antonio the value of pcie_type seems
to be PCI_EXP_TYPE_ROOT_PORT and from the available types I think that
PCI_EXP_TYPE_PCIE_BRIDGE is also possible.

Thanks,

	Joerg

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