libpciaccess bogus bridge data - commit 2bda5b73

Jesse Barnes jbarnes at
Mon Dec 6 09:35:48 PST 2010

On Wed, 1 Dec 2010 18:54:22 -0800
Bryce Harrington <bryce at> wrote:

> Jesse,
> I have a question about change 2bda5b73 that you did to libpciaccess
> last year, to stop pci_device_get_bridge_buses() from looking at bus
> data if the bridge data was not read.
> A ubuntu bug reporter says that this check is preventing his device from
> getting detected properly - see
> Looking at the code I see that for case 0x04 there's already a check for
> NULL, where it attempts to re-read the bridge info, so presumably there
> are at least some situations where NULL bridge.pci is expected?
> What I'm wondering is if the check should be less strict in cases of
> multi-function cards, or if somewhere else in the code needs updated to
> read these devices properly.

The multifunction check is probably ok, but there should still be a
bridge above the device regardless, even if it's just a host bridge I
think, so we should figure out why that's not getting set...

Jesse Barnes, Intel Open Source Technology Center

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