There are some 0 resource size pci devices, and it leads to the accumulator fails to maintain the correct value. It results in a strange issue on my machine that xhci_hcd failed to init. [ 2.437278] xhci_hcd 0000:05:00.0: init 0000:05:00.0 fail, -16 [ 2.437300] xhci_hcd: probe of 0000:05:00.0 failed with error -16 To fix this, check if the resource size equals to 0, doesn't increase size. Fixes: c9c75143a596 ("PCI: Fix calculation of bridge window's size and alignment") CC: stable@xxxxxxxxxxxxxxx # 4.14+ Signed-off-by: AceLan Kao <acelan.kao@xxxxxxxxxxxxx> --- drivers/pci/setup-bus.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c index 79b1824e83b4..ae05dde8c6e3 100644 --- a/drivers/pci/setup-bus.c +++ b/drivers/pci/setup-bus.c @@ -1061,7 +1061,8 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask, r->flags = 0; continue; } - size += max(r_size, align); + if (r_size != 0) + size += max(r_size, align); /* Exclude ranges with size > align from calculation of the alignment. */ if (r_size <= align) -- 2.17.1