diff options
| author | Mika Westerberg <mika.westerberg@linux.intel.com> | 2022-09-05 11:02:27 +0300 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2022-09-20 18:19:11 -0500 |
| commit | 8066cc86b7aaaf6b4b38a81932459c6450440daa (patch) | |
| tree | 2e754943d54569e9de2c836ba2ffd2bc97ea8899 /drivers/pci/probe.c | |
| parent | 568035b01cfb107af8d2e4bd2fb9aea22cf5b868 (diff) | |
PCI: Fix used_buses calculation in pci_scan_child_bus_extend()
pci_scan_bridge_extend() returns the subordinate bus number needed to cover
all the buses below a bridge. pci_scan_child_bus_extend() computes the
number of buses to reserve by comparing that with the current max bus
number. Previously it did the subtraction in the wrong order, so
'used_buses' was nonsense.
Subtract 'max' from 'cmax' as is done for the similar
pci_scan_bridge_extend() call in the following block.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216000
Fixes: 3374c545c27c ("PCI: Account for all bridges on bus when distributing bus numbers")
Link: https://lore.kernel.org/r/20220905080232.36087-2-mika.westerberg@linux.intel.com
Reported-by: Chris Chiu <chris.chiu@canonical.com>
Tested-by: Chris Chiu <chris.chiu@canonical.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Diffstat (limited to 'drivers/pci/probe.c')
| -rw-r--r-- | drivers/pci/probe.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index c5286b027f00..4f940dcd102c 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -2920,8 +2920,8 @@ static unsigned int pci_scan_child_bus_extend(struct pci_bus *bus, * hotplug bridges too much during the second scan below. */ used_buses++; - if (cmax - max > 1) - used_buses += cmax - max - 1; + if (max - cmax > 1) + used_buses += max - cmax - 1; } /* Scan bridges that need to be reconfigured */ |