The addition of the bus_info field did not account for the fact that the
PCI bus can be scanned multiple times (like for device hotplug and other
uses in SPDK).
Indeed, during pci_scan_one() for devices that were already registered,
the pci_common_set() overwrites the bus_info field, leaking the
previously allocated memory.
Since the bus_info content is fixed for a PCI device, we can simply skip
allocation if dev->bus_info is already set.
Fixes: 8f4de2dba9 ("bus/pci: fill bus specific information")
Reported-by: Tomasz Zawadzki <tomasz.zawadzki@intel.com>
Signed-off-by: David Marchand <david.marchand@redhat.com>
db4092276a